Main Page
Welcome to the explain xkcd wiki!
We have an explanation for all 3103 xkcd comics, and only 99 (3.2%) are incomplete. Help us finish them!
Latest comic
Reading a Big Number |
![]() Title text: [desperately] Maybe this is from some country where they use commas as decimal points, and also as digit separators after the decimal, and also use random other characters for decoration??? |
Explanation
This comic expresses Randall's reactions to reading large numbers. It starts with normal digits and commas you would find in a large number, but gradually becomes more and more chaotic. It turns out that this is not a number at all, but some sort of printing error in whatever Randall is reading.
The very start of the comic is a bit absurd. In most cases, you can tell that a number like this is very large because of how long it is when written out; you wouldn't have to completely reinterpret it at the end of every group of digits. However, to tell exactly which "-illion" the number falls into, you would have to count the groups, and the scale of such a large number would grow less familiar as you try to keep track of how large it even is. Certain sizes of numbers tend to show up in specific contexts, like astronomy. So, rather than literally showing Randall's developing thoughts on the evidently massive size of this number, the comic also shows how he tends to interpret numbers at each possible "-illion" scale.
Number fragment | Thought | Explanation |
---|---|---|
54 | 54! Great! I know that number. Solid start. | 54 is a number with some real-world familiarity for most people. It is small enough to appear on digital clocks, and has enough factors to be listed on standard multiplication tables as 6 × 9.
Randall pretending to reckon with the start of such a large number is probably meant to draw attention to the meaninglessness of doing so. Unless the exact value is somehow important, most readers wouldn't find much of a meaningful difference between "54 zillion" or "over 50 zillion", or even "zillions and zillions". In practice, the brain can only approximate numbers this large; the threshold needed to tell the difference between the amounts that they represent is too high. Randall expresses a similar sentiment once he gets to the trillions and quadrillions. |
,000 (thousand) | Oh, a comma and some zeros. Cool. Must be at least 54 thousand. | Underselling how long the number is with the "at least a thousand", but is a fair thought from the POV of not being able to know how long the number is. |
,000 (million) | A second comma! I wonder if we're talking population or money. | Excitement from how large the number must be. Populations (like the number of people in a region) and large sums of money are both often measured in millions. |
,000 (billion) | Yikes! If this is money, it's a lot of money. | Three commas means a number in the billions. That's a lot of money for one person to have. Big decisions by large corporations, such as megamergers, are often measured in billions of dollars in costs. |
,000,000 (quadrillion) | Why am I reading this? Whatever this number is, I'm not going to be able to visualize it. | Five commas is a number in the quadrillions. At this point the number is too big for human minds to comprehend. |
,000 (quintillion) | All right, either someone made a unit conversion error or this is one of those incomprehensible astronomy numbers. | Astronomy often deals with extremely large numbers due to the incredible scale of the universe. For example, the distance to the Andromeda galaxy in kilometers could be numbered in quintillions. Alternatively, the person calculating the number made a mistake. |
,0000 (!?) | Oh no. Is this a misplaced comma or an extra zero? I guess we'll see if the next group has two zeros or three. If it's two, we can at least hope the digits are right. | Commas are placed every three digits in typical western usage (although not necessarily in various other cultures), so something is wrong. However, it might simply be that someone misplaced the comma to the right, meaning that this group has four digits and the next one would likely have two (the next comma in the 'correct' place). If the next group is three, then either the commas are now all misplaced or possibly someone/something just doubled up a zero by accident. A mistake of any kind makes one think that the number may not actually be accurate but, if the former, at least it might just be a relatively unimportant transposition. |
,0000 | Oh no. | A second group of four zeroes means it's not a typo. Something is seriously wrong. Note that some countries like China or Japan (where 4-digit groupings are common) or India (which uses a unique 2- and 3-digit mixed system) may use non 3-digit groupings, but have their own rules for number groupings. |
,054 | What is happening. | Big numbers are normally rounded, so it's very strange to see a non-zero value this far down in the place values. Also, "54" matches the digits at the start of the number so it could indicate the number was copied incorrectly. The non-zero digits here imply that all of the digits so far, including the zeroes, are significant figures; the number is not only extremely large, but implausibly precise with at least 30 sig figs. By way of comparison, the diameter of the observable universe is about 4.4 × 1026 m, and if that measurement had 30 sigfigs, it would be precise to about half a millimeter. |
,000"000 | Someone messed up real bad. | The arcsecond mark " indicates that this number is an angle or a distance in inches. For an angle, even accounting for how small an arcsecond is (1/3600th of a degree), this angle would be a huge number rotations. As for inches, it would represent a distance much larger than the observable universe, it is also uncommon to use customary units like inches in conjunction with large numbers. Alternatively, this could be "to-the-11th-power", which would make the already extremely large number extremely ridiculously big. This could also be a sign of bad copy-pasting, where the quotation mark " was accidentally copied along with the large number but not with a matching one. Or if this number was being printed from a computer program, the mark may be a sign that the closing quote around a computer string was accidentally escaped, causing it to become present in the string rather than indicating the end of the string. |
,00c2ef46 | Someone messed up real bad and I hope it wasn't me. | Numbers normally only use the digits 0-9. The use of letters suggest that this is a hexadecimal number. Angles are not normally expressed in hexadecimal. Hexadecimal is mostly used by computers, so Randall, as a programmer, might be worried that the hexadecimal appearing is his fault. Seeing a long string of unexpected characters may indicate a memory bug, such as a buffer overflow. These bugs can lead to crashes, data corruption and security vulnerabilities, and Randall would rather not be responsible for it. |
(title text) | [desperately] Maybe this is from some country where they use commas as decimal points, and also as digit separators after the decimal, and also use random other characters for decoration??? | In the United States, UK, India, China, Korea, Japan, and other countries, the dot is used to separate the integer part of a number from its fractional part. However, most of mainland Europe and South America uses the comma for this purpose. In some places, one may also see the period used to group digits. Since the final number is unreadable and potentially infinite, this implies that Randall has, naturally, made up an explanation instead of trying to figure out what was really happening. |
There are a few possible explanations for seeing a number like this appear in a software application. It may have appeared due to an out-of-bounds read operation where the computer tries to interpret unrelated data as text. Another possible explanation is misuse of the printf function in the C programming language. If strings passed to printf do not contain a null byte to terminate the string, it will go further into memory, again into unrelated data. Or the programmer might have several printf statements back to back, forgetting that printf doesn't add newlines (like the println function in other programming languages), so all their debug information gets printed on the same line.
Transcript
- Thought Process While Reading a Big Number
- 54,000,000,000,000,000,000,0000,0000,054,000"000,00c2ef46 [continuing off the edge of the comic]
- [At various points on the number, a line is connected from the number to a note]
- [Before first comma] 54! Great! I know that number. Solid start.
- [After first comma] Oh, a comma and some zeros. Cool. Must be at least 54 thousand.
- [After second comma] A second comma! I wonder if we're talking population or money.
- [After third comma] Yikes! If this is money, it's a lot of money.
- [After fifth comma] Why am I reading this? Whatever this number is, I'm not going to be able to visualize it.
- [After sixth comma] All right, either someone made a unit conversion error or this is one of those incomprehensible astronomy numbers.
- [After seventh comma (first group of 4 zeros)] Oh no. Is this a misplaced comma or an extra zero? I guess we'll see if the next group has two zeros or three. If it's two, we can at least hope the digits are right.
- [After eighth comma (second group of 4 zeros)] Oh no.
- [After ninth comma (second 54)] What is happening.
- [By quotation mark] Someone messed up real bad.
- [By mixed alphanumeric numbers] Someone messed up real bad and I hope it wasn't me.

New here?
Lots of people contribute to make this wiki a success. Many of the recent contributors above have just joined. You can do it too! Create your account here.
You can read a brief introduction about this wiki at explain xkcd. Feel free to create an account and contribute to the wiki! We need explanations for xkcd comics, characters, What If? articles, and everything in between. If it is referenced in an xkcd comic, it should be here.
- If you're new to wiki editing, see the explain xkcd:Editor FAQ for a specific guidance to this wiki and the more general help on how to edit wiki pages. There's also a handy wikicode cheatsheet.
- Discussion about the wiki itself happens at the Community portal.
- You can browse the comics from the list of all comics or by navigating the category tree at Category:Comics.
- The incomplete explanations are listed here. Feel free to help out by expanding them!
Rules
Don't be a jerk!
There are a lot of comics that don't have set-in-stone explanations; feel free to put multiple interpretations in the wiki page for each comic.
If you want to talk about a specific comic, use its discussion page.
Please only submit material directly related to xkcd and, of course, only submit material that can legally be posted and freely edited. Off-topic or other inappropriate content is subject to removal or modification at admin discretion, and users who repeatedly post such content will be blocked.
If you need assistance from an admin, post a message to the Admin requests board.