John Titor

John Titor & The IBM 5100

In 1975, IBM released the first mass-produced portable computer, the 5100.

It was an incredible feat for the time: An integrated 5-inch CRT monitor, up to 64 kilobytes of random-access memory (RAM), and the ability to run programs meant for larger, more expensive computers, all in something the size of a briefcase.

In fact, the IBM 5100 was extraordinarily close to becoming the world’s very first Personal Computer, a title taken a few short months earlier by the Altair 8800.

But the IBM 5100 was more than just a portable computer. It contained a hidden feature that remained undiscovered by the general public for fifteen years, until the year 2000.

The year John Titor supposedly arrived on our world-line.


John Titor’s story began in the year 2036.

Titor belonged to a team of seven individuals selected to embark on a journey through time. He had lived through unimaginable horrors in a world destroyed by selfishness, cynicism, and corrupt government, ravaged by nuclear war.

To make matters worse, what little remained of their technology was threatened by a looming UNIX timeout error in 2038.

An IBM 5100 was just what they needed. It’s ability to debug and emulate code between various programming languages made it an important component in keeping the technological architecture of their fallen world alive.

Unfortunately, none could easily be found in 2036.

And so Titor’s mission was straightforward: Travel to 1975, using a rudimentary time machine, and acquire an IBM 5100 portable computer.

IBM 5100 To The Rescue

While this is only one very small part of the John Titor legend, it seems to be the genesis for the entire myth. Looking at it as a story, without the 2038 timeout and the need for an IBM 5100, Titor would have never been sent on his mission through time.

And what’s interesting is, for all intents and purposes, time travel notwithstanding, it’s very much grounded in reality.

We need the system to “debug” various legacy computer programs in 2036. UNIX has a problem in 2038.

– John Titor

The IBM 5100 did, indeed, contain functionality that was hidden from the public. At a time when most computers could only support the BASIC programming language, the IBM 5100 had the ability to emulate programs in both BASIC for system/3 and APL for system/370 (the “system” in this case refers to IBM mainframes). According to Bob Dubke, one of the IBM 5100 engineers, this function was hidden “because of worries about how [IBM’s] competition might use it.”

That piece of the story is verifiably correct.

Even if the function weren’t hidden, however, the general public, especially around 2000-2001, most likely had little idea that such a machine even existed. Whoever the individual posting as John Titor was, he knew his stuff.

So, if the UNIX timeout of 2038 is to be a serious problem, and if in 2036 we require the ability to “reverse engineer” or debug certain code to prevent a technological apocalypse, a 5100 could be our go-to machine.

The Unix Timeout Of 2038

The UNIX timeout, by the way, is a very real concern.

A timeout error is caused by the way computers count system time. They count time not by actual dates — months, days, or years, as we do — but rather by seconds.

The problem is that computers also have a limit to how high they can count. So, when they reach that limit, various problems may occur.

The 2038 UNIX timeout in particular stems from the limitations of computers using signed 32-bit integers. Once these 32-bit, UNIX-based computers reach their limit at 03:14:07 UTC on Tuesday, January 19, 2038, they will encounter something called a 32-bit overflow.

From that point, the date on these machines will be interpreted as 1901.

This will cause operating systems and certain software to malfunction, unless we successfully prevent it from happening.

This issue isn’t only limited to UNIX-based computers, either, as any computer or software that relies on a 32-bit integer, as well as the UNIX epoch, will reach the same error (it should be noted that 64-bit machines, which are becoming more common these days, won’t suffer the 2038 UNIX problem).

The Y2K bug was surrounded by very similar circumstances, and such errors have even temporarily brought down commercial software and devices. The Microsoft Zune, for example, was the victim of a leap-year glitch, which caused Microsoft Zunes around the world to freeze at about 1:30 a.m. ET, Wednesday, December 31, 2008.

These errors, while troublesome, were clearly fixable. We’ve yet to see the implications of the UNIX timeout in 2038.

And that’s the thing about John Titor: Even though most of his “predictions” have proven false, like any good urban legend, his story contains many elements of truth. There’s even a profound moral message and warning: Change your ways, or things will go badly.

That, and maybe it’s time to upgrade your computer.


Rob Schwarz

Rob Schwarz is a writer, blogger, and part-time peddler of mysterious tales. Editor-in-chief of Stranger Dimensions.


  1. 1998 i have many ibm 5100 all set to go linday kelsey and rudy meyering and dan forte just want to get rid of these machines in call in center in toronto at 105 moatfield drive in don mills and york mills area northwest corner behind prince hotel help yourself in year 1998 if you are truly a time traveler and go save the year 2036 ….

    1. Daniel, you made a terrible mistake. I am Zorg from the Undercover Alliance and, as part of our plan to spread chaos in 2038 and raise to power as the only hope for mankind’s salvation, I have to destroy all ibm 5100 computers. So, me and my minions are going to meet you, Lindsay, Rudy and Dan in 1998, and our phasers aren’t set to stun…
      (Wait! Check this box if you’re human) well, I am not a human but I will check it anyway.

  2. The reason why John`s statements are sometimes false and/or true is becasue everytime he stumbles back or forward through time he might not land on the same timeline meaning if he went back to the assassination of Lincoln and stated he was killed by a colt 1851 navy, then that would be false he was actually killed by a 1858 Whitney revolver but he still saw the death of lincoln; every single timeline have similar occurances but the time or fashion that they happen in might vary!

    1. he even mentioned about football team which win in x timeline… but lose in y timeline … even in the same date… multi dimensional interpretation

      1. John Titor is still mystery about him tho.. Well i tried to research some parts of his IBM 5100 and it shows how it build and well made to Time Travel , That machine manipulates Time and Space through time while traveling to another world lines theres tons of world that u will be entered and it cannot be only 1 world because the Universe Has the beginning but no end It means there might be a multiple of us living in the different dimension. I am still curious about in 1975, he tried to obtain the IBM 5100 portable computer and what after what he will do about it change the world lines? without altering the established event of the World Hmmm… That may be a quite possible but the way he act and the way he moves have sense and never have been wrong Only based on my Observation. Thank you For listening to my Research even my Grammar is bad because im still not used to it.

    2. I totally agree with you. I do believe that tutor came from the future but not from the same world line as us. Let’s say there was a beta and an alpha world line. We might be currently in the beta world line while titor was in the alpha world line when everything he said happened.thats why some of the things he say may not be true in the exact way but could be happening just in a different way. So when he time traveled he switched world lines without realizing it and that’s why the stuff he says aren’t all true. Basically all world lines are different. I believe you can experience some memories from a different world line by having a de ja vu moment. You felt like that has happened to you before which it might have just in a different world line.

  3. its about like andrew said in his interview on coast to coast, when he went to the future to see what would happen in 2012 and he stated that there was something terrible that happened to DC but when in fact DC is stil lon the map, so either what they did by sending someone there or by fixing something caused that happenening to fail but it doesn`t mean that it won`t happen in the upcomming futur!

  4. Actually, even if the author of the John Titor story is a hoax, regardless of such, many of his predictions did in fact / have come true. RHIC discovered mini-black holes. The towers in New York fell. Tensions have increased to the brink of conflict, etc. Further, the Fighting Diamondbacks are real. It all depends on how YOU interpret the story, and again, regardless / despite whether the ‘story’ is true/untrue / fact/fiction / real/hoax … much of what he wrote IS and HAS in fact materialized as true. Simply writing that predictions from the story of John Titor haven’t come true does not, I repeat, does not, in any scientific way shape or form invalidate what he wrote. Some times fiction becomes fact and DEEPER TRUTH is often FAR STRANGER than any work of fiction. Period.

    1. the stranger thing is not about whether his “prediction” is becoming true or not… but he mentioned lot of time machine principle… which is all scientific fact/formula… and theory / formula he mentioned… only Doctoral physicist who could understand… because he talked about quantum physics

  5. I came across this quit by accident and was captivated as much by the name “John
    Titor” as I am by the subject matter. Obviously it is a well-crafted pseudonym.

    “John Titor.” This is a very clever and fitting pen name for the occasion, the perfect pseudonym on so many different levels; one that, under the circumstances, I believe is being used by a learned, creative and enlightened individual; whether a learned, creative and enlightened time traveler, we will just have to wait and see what transpires in Washington DC at 3:45 AM on March 12, 2015.

    The “time traveler’s” given name, “John,” is associated with prophecy; it features
    prominently with the revealing or disclosing of some truth or privileged knowledge. For example, the Gospel of John is highly prophetic with events to come, and of course there is the Book of Revelation, also known simply as the “Apocalypse,” alleged to have been authored by “John of Patmos” (also called “John the
    Revelator”). The two most important books in the Christian tradition involving
    revelation are attributed to someone named “John.”

    His surname, “Titor,” translates to “Τίτος” in Greek, and “Τίτος” translates to Titus
    in English. In the King James Bible, Titus 3:10, we read: “Warn a divisive person once, and then warn them a second time. After that, have nothing to do with them.” And Titus 2:12: “Teaching us that, denying ungodliness and worldly lusts, we should live soberly, righteously, and godly, in this present world.” “Titus” in its entirety is applicable, actually.

    In the Galician language, “Titor” means Guardian/Teacher/Tutor. I would
    very much enjoy engaging in some Dialectical Materialism
    with our prophetic guardian from the future.

      1. None of what Titor predicted has come to pass, in terms of civil war and all that, however, Titor did say that our timeline, in relation to his may be slightly different due to any number of events. If we look at where we are today, we may actually be on the edge of what he predicted. Either way, whoever Titor was/is, he was brilliant!

      2. HIs timeframes have been off (which he even admitted may happen) But CERN has now created microsingularities.

        Also, his reasons for what caused the civil war and subsequent WW3 are eerily reminiscent of what we are seeing right now.

      3. Not only that.

        2015 wwIII can be predicted as the dozens of syrians who died during the war or on the way to west europa.

        Also when you look at wikipedias timeline for 12 may 2015

        There is something associated with CERN.

        There is nothing on 12 may 2015 happended in washington but this is evedience enough.

        But his prediations like the one with the worlwar which means the death of the syrians were also 1000 years ago predicted from other sources so it really could be a big hoax.

      4. There’s also something called ‘Ascension’. You, I, and whoever reads this, are choosing a peaceful timeline, where we can eventually realize our full divine potential and become the creators of our reality. Hence wars aren’t a part of our scenario. Full stop.

      5. i’ve not been able to find anything. so far, anyway. but since we’re still here, i’m assuming that at least on our timeline “all is well”, or at least snafu.

  6. For all i know;John Titor could have never been a time traveller
    and just a person with pretty good intellectual about what the future could be like…
    i say this considering some of the facts he says
    he talks about the computer systems,but not the laptops…advanced communications systems like cells…but nothing like touch screen phones were ever told,.he discussed about the television saying cathode ray tubes are out but the crystals and plasma’s come in, totally forgetting about the LED’s which are currently used
    the computers,cell phone net,LCD and Plasma were some of the terms that were developed around that time period.(2000-2001)
    The person named John Titor who was claiming to be a time traveller,could have been studying all the physics related in depth and very well answered with questions avoiding all other possible questions which he could not answer for that time being by sheer psychological mind tricks, saying he didnt want to change any possible outcomes of the future by sharing the information which may benefit any person or avoid his or her fate.
    And from most of his comments it would seem like he was doing all that just to entertain himself whether or not he knew anything.
    He mentions the CERN in many of his comments but never the Large Hadron Collider…he could even say it in short LHC to avoid any possible usage of that terms by others
    When it comes to the time machine he would go on explaining everything even the physics stuff…but regarding the remaining theories…he always skips answering saying he is not a physicist.
    One more thing keeps me bugging, he entered military at the age of 13 and college at the age of 31…….exact opposite of each other using the same 1&3 digits….It might be just a co-incidence
    Saying all this,a part of me still thinks he might really have been from future

    1. john titor never mentioned about LHC… but talking about “atom smasher”, sub atomic particle, Kerr type singularity,wave particle duality, and hundred more term and formula ( read John Titor patent about Time machine)… if you read carefully about physics he talked about… you realize that he is talking about quantum physics… only Doctoral Degree who cound understand it ( or they who study quantum physics autodidact )

      1. it was NOT the 90’s!!!!! 2000 is not part of the 1990s decade it’s part of the 2000s decade!

      2. I don’t think so. I understand a great deal about quantum physics and I don’t have ANY degree. I think it would only require someone with a high IQ and a knowledge in that particular field of interest.

  7. so if we keep an IBM 5100 somewhere and in the year 2036 we use that computer to fix the bug in UNIX..wouldnt that alter 2001 because Mr TItor wouldnt have had a reason to come back therefore, none of this ever happend and we shouldnt have known who John Titor is at all because the past and the future keeps repeating it self ….OR HOW THE HELL DOES TIME TRAVEL EVEN WORK

    1. No I think it would just stop the 2038 event from happening but traveling back to 2001 would re write every thing that has happened from 2001 to 2036. Just one little thing changed such as crossing a street will effect every thing.

      1. And if he travelled back to 1960, Dick Nixon would have known better to shave and put on makeup for the camera – and get a fan. And to throw away the Dictabelt machines….No Kennedy, no LBJ OR Vietnam. Just Dick.

    2. technically we could fix the bug now, actually…. we are already replacing our systems with machines that are immune to the bug….. js.

    3. and titor whoever he is, described very well how time travel works. while I am convinced titor is a hoax, I believe he was right about his theory. Well, technically it’s Tipler’s theory.

  8. While the “general public” was not aware of the so-called “hidden
    functionality” of the IBM 5100…every computer geek alive in the late 70s definitely was. Hell, I stated playing with computers in 1982…and a IBM 5100 was still
    considered a prized piece of equipment at that time…simply because of it’s emulation and debug capabilities.

    This tells me that, Titor, like myself, is an aging computer geek that was likely born in the late 60s early 70s…who would have become well aware of the value of the IBM 5100 during the 80s. However, there are many machines available today, that are actually built for the expressed purpose of emulation and debug software, and do such functions much fast and more efficiently than the IBM 5100…so going back 61 years to retrieve the “stone knife” of computers seems a little silly…when only a 10 or 15 year trip would have been necessary to get a much more advanced piece of equipment. The shorter trip would also reduce the common “1-2.5% divergence” of the timeline, that he so often mentioned, to less than .030% …at least according to his imaginary mathematics.

    As for the “UNIX 2038 Bug”…again, it is something that serious computer people have known about for many years. In fact, we knew all about it way back in 1981…just like we did with the Windows Y2K bug. Again, implying that Titor is merely an aging computer geek.

    If you recall, the media had everyone freaking out over the Y2K bug…but computer people were telling everyone it was not that big of a deal, and that the world was NOT going to come to a screeching halt at 12:01am January 1st , 2000 over that issue. When the time came…patches were issued and the problem was solved and only a few minor glitches took place around the world…on unpatched systems beloning to idiots who simply didn’t listen to reason.

    We have another 24 years to patch the 2038 bug. However, computer manufactures have all changed over to 64Bit hardware…which will be completely unaffected by the 2038 UNIX issue. I find it hard to believe that in another 24 years, that any 32Bit systems will even exist…nor will 64Bit systems for that matter. The 2038 UNIX bug is simply a non-issue due to the changes in hardware that have, and will continue, to occur in the next quarter century.

    Finally, I find it EXTREMELY hard to believe that a society capable of creating micro-singularities, then containing and harnessing the power of those singularities, to power a device to allow them to travel through time…would need to use it to retrieve an ancient IBM 5100 just to solve a software clinch. Seriously, in today’s terms, that would be a little like me sitting in a room full of laptops running i7 processors…and using a Madas 20BZS desktop calculator (circa 1954) to do my taxes. Wouldn’t it be more logical to use such technology to go back in time and alter the events of history, so that the Civil War and the following nuclear war never happened? I mean if you are going to contaminate the timeline…why not just go all out?

    Personally, I think Titor was an older computer geek, as shown by his knowledge of the IBM 5100’s capabilities and the existance of the 2038 UNIX bug….but he was also, obviously, a fan of Star Trek: The Next Generation”…because, according to the show, Romulan Starships are powered by “artificial micro-singularities”.

    Face it people, Titor was not a time traveler. He was just guy with a little extra time on his hands, who posted a bunch of BS on the web to see who was gullible enough to fall for his BS…and he was obviously quite successful, because people are still talking about him 14 years later..

    1. He would needed to have paid US$19,975.00 in cash with bills that were issued 1975 or before hand it would of been impossible for him to pay with credit card for the merchant would need to call in and retrieve the Authorization number so a dummy card would not of worked.

    2. his grandfather are one of the team who build IBM 5100… and he directly go to that year to meet his grandfather personally… and ask him for this machine… so he doenst need to buy or even steal

    3. If I had access to time travel technology, and I wanted to send someone back to fix something, I would have briefed him on that being the stated mission, but the actual mission would something else that brought us where we are now. Titor wouldn’t even need to know, he’d just have to do some small thing that would have the expected impact. He’d probably never realize the truth, honestly. It’s better that way. You don’t want to risk the possibility of a time traveler with real knowledge being intercepted.

    4. 3 years late for this comment, but I think I need to add this: I don’t think people really care if he’s a time traveler, it’s just that there was actual thought put behind it to make it feel real, so the ideas and theories sparked good conversation around it. Kind’a like the zombie apocalypse – there’s 0 chance for that happening, yet a ridiculous amount of people find it fascinating.

      For me, real (if you chose to believe it) or not, the most important thing we got out of all this was Steins;Gate.

  9. This is a simple fact how come the United States government could notacquire a IBM 5100 from a private home or a collector in 2036. Soon as John T went back to 1975 and touched that IBM 5100 which was September, 1975. Price: US $19,975 w/ 64K RAM. Weight: 55 pounds. CPU: IBM proprietary, 1.9MHz. RAM: 16K, 64K. He would needed to have paid with cash money predated 1975 or 1975 in cash money or pay Credit Card but how would that of happened if he had a Credit Card created in 2036 as dummy document Master Card, Visa, Dinners Card etc would need a authorization number to verify the 19,975$. Then transporting this Computer to the future just even purchasing the computer in the store could re write every thing in the future that will ever happen.

    1. The luggage fees on transporting the computer would be tricky. Also, in 1975, he’d be more inclined to use his Bank Americard or Master Charge. Plus, all those re-capped capacitors…and what if the CRT tube gives out just as the computer spews out the code. MacGruber!

  10. its not about 64 bit processor… but about little software that count the date,clock… this unix 32 bit clock system are not exclusively unix… but also linux and windows… in microcontroller world, this problem solved by counting date and clock with different starting year… 2000 pick as start year… so RTC microcontroller / embedded system will “survive” until 2099

  11. John Titor is/was undoubtedly a clever man who knew quite a bit about a lot of things. My guess is that–yes, he is a computer expert as someone here points out AND that he somehow is/was able to see into the future through most likely Remote Viewing or some form of prediction. Or maybe John Titor was more like a group of people trying out their remote viewing/ mass hypnosis etc..skills on the masses, or even some sort of psych. project looking to see how gullible people can be, or how much we are willing to believe. It was too perfect for it to be just one lonely guy playing around with the internet. The truth is out there, it´s just not what we think it is.

  12. Wait… so the whole John Titor thing is real?

    I’m at a complete loss for words right now. I thought it was completely made up for Steins;Gate. I didn’t know this was a real thing happening in our world. This just goes to show how Steins;Gate is even more of an incredible show. I truly recommend it to every single one of you here. I don’t like anime at all but I must admit it is the greatest story I have ever come across yet.

    1. John Titor first appeared on the old BBS news-threads back in the early 1990’s. He really achieved fame when Coast To Coast with Art Bell talked about him. He disappeared just as mysteriously as he appeared.

      1. he did NOT appear in the early 90’s. He FIRST appeared by sending Art Bell a fax in 98. He didn’t start posting on forums until the year 2000. dummy

    2. I deeply agree. I was shocked when after searching up John Titor, it seemed as if he was actually real! I’m only on episode 14, but I am now completely obsessed with time travel and how the IBM 5000 could actually a outlet to time travel. Hopefully it will wear off once i finish the anime, since i have no one to share the excitement with. You should also consider watching more mystery animes, its really not all that bad. TIME TRAVELL

  13. Hide the truth in the lie. We just have to read between the line !

    Maybe it’s a traveller or not but some prediction still impressive and disturbing.

  14. whoever this guy was he really knew a lot about computers

    Ive found the story fascinating and after doing my own research etc I have concluded that if he wasnt the real deal he was probably a computer science professor,

    That IBM 5100 thing and the 2038 problem in particular are not very well known things to the public…. IBM especially takes a alot of care when it comes to proprietary info like that…..

  15. Literally no one on the planet cared about APL/370 except for a small community of actuaries.

  16. I own a 5100 bought by my father, who worked at IBM Endicott ny . It is in perfect condition and still have programs I wrote in APL when I was 7-14 years old. Taught by my dad a APL programmer who also worked for PING and Lou Solheim also a APL programmer. It works as new and has been in the same house for over 40 years.. Is it worth anything.

  17. Why not just make the computer. It’s from 1975, surely you can recreate a rudimentary computer system if you can make a time machine. Doesn’t need to look the same. F it! Put a touchscreen on or a hover keyboard. John Titor/basement dweller

  18. Maybe this is an example of the Mandela-Berenstain Bears thing, but I was sure I heard about the APL abilities of the IBM 5100 in the early 1980s and it is indeed listed in a number of pre-2000 computer history books . . . in fact the US$19 950 version of the machine has a switch on the console to switch from Basic to APL, and the $9 000 versions were Basic or APL. That is where I saw my first APL programme back in the day.

    Was, as I heard when I first learned of the Titor story, the hidden ability was the potential to also run and debug Algol/Jovial, Cobol, Fortran, PL/I, and possibly Forth and BCPL and/or C? Maybe also assorted mainframe, minicomputer, supercomputer and Intel 80* processors’ assembly language and/or machine code? That would make more sense — I am sure the proportion of mission critical software written in APL still extant these days is at the low per myriad range or even less, and I think the first Unix APL compiler did not appear until well after 1975 and APL and Basic variants are very uncommon systems programming languages, if at all.