Input
Preparing your workspace…
How to use
- Choose a source and destination base, then enter one number per line.
- Compare the main result and the common-base values.
- Copy a result or download the batch with its row errors.
The same value in a different base
A numeral’s base determines the value of each position. Changing the base rewrites the same mathematical value; it does not encode a text string or change a byte order.
Compare four common representations at once or choose any input and output base from 2 to 36. Letter digits are case-insensitive on input.
Representations and workflow
Signed numerals and matching 0b, 0o and 0x prefixes are accepted. An underscore may separate digits, but spaces inside one numeral are rejected. For bases above ten, A through Z supply the remaining digits.
25511111111Decimal 255 equals binary 11111111, octal 377 and hexadecimal FF.
Precision and validation
Integers are processed with BigInt rather than floating-point numbers. Fractions use an integer numerator and denominator. A repeating expansion stops at the chosen precision and is labeled truncated; the displayed digits are not rounded.
Interpreting and reusing the result
Batch mode preserves input order, including invalid rows. The output has an empty line for a failed row and Copy results is disabled until every row is valid; JSON includes the diagnostic code for each error.
Numbers: up to 500 lines / 1 MiB, at most 4,096 characters per numeral. Fraction output: 1–128 digits. Text and byte data: 64 KiB. Bitwise operations: 8–256 bits. Workers stop after 30 seconds; inputs are not uploaded.
Frequently asked questions
Can I convert a number in base 36?
Yes. Select base 36 and use digits 0–9 and letters A–Z. Letter case does not affect the value.
Will a 64-bit integer lose precision?
No. Integer arithmetic uses BigInt throughout, including values larger than 2^53 − 1.
Why does a fraction show Truncated?
Some fractions repeat in the destination base. The tool stops at 1–128 fractional digits; copied output contains exactly the displayed digits.
Is my input sent to a server?
No. Computation runs in a browser worker. DevToolsy does not upload or store your input.
What does Copy include?
Copy exports the selected displayed value. Download JSON preserves strings and diagnostic codes; it does not turn large numbers into floating-point values.