All tools › Bases and machine numbers
Number base converter
Any base from two to thirty-six, with no ceiling on the number and the fraction included.
It runs entirely in this browser tab: what you type is never uploaded, and the tool makes no network request while it works. Open your browser's network panel and try it — nothing leaves the page. There is no sign-up and no limit beyond what your own browser can hold.
Settings
- Read in base
- A prefix in the number itself wins over this. A number from 2 to 36.
- Also show base
- Two, eight, ten and sixteen are always shown. A number from 2 to 36.
- Decimal places
- How many digits after the point. A number from 0 to 64.
- Space every
- Digits per group. Four lines a binary number up with the hexadecimal one; zero groups nothing. A number from 0 to 16.
- Show the working
- Replaces the answer with how it was arrived at, step by step.
How to use it
- Paste your text into the box above, or open a file.
- Adjust the settings beside it until the result is what you wanted.
- Copy the result, or save it as a file. The result updates as you type.
Questions
- Is what I type uploaded anywhere?
- No. This page carries the whole tool as WebAssembly and runs it on your own device. Nothing you type is sent anywhere, and there is no network request to make while it works.
- How exact is the arithmetic?
- Exact, in decimal, for everything the tool was given: no value here is put through floating point on the way to the answer. Where there is a genuine ceiling — thirty-nine digits for the number-theory tools, a fixed number of places for a repeating fraction — the tool says the limit rather than quietly truncating.
- Can I get this result again later?
- The settings travel in the page's address, after the #, so a link reproduces them exactly — and the fragment of an address is never sent to a server. Your last settings are also remembered on this device, which is worth knowing before you paste a number you would not want left there.
- Is there a version that is not a web page?
- Yes. The same tools are built as a desktop application from the same code, with a save dialog instead of a download and no network code at all.
Other tools for bases and machine numbers
Roman numeral converter
Both ways, a whole column at a time, and it reads the clock-face spellings too.
Binary calculator
Adds, subtracts, multiplies and divides in base two, with the columns written out.
Hex calculator
The same arithmetic in base sixteen, which is how an address and an offset are written.
Bitwise calculator
AND, OR, XOR, NOT and the four shifts, with every value laid out as bits.
Two's complement converter
How a machine stores a negative number, in any width, with the range beside it.
IEEE 754 float converter
Why nought point one is not nought point one, shown as all fifty-five digits of what was stored.
All thirty-one tools