Hex ↔ String Converter
Convert text to hexadecimal and hex back to readable text, UTF-8 aware. Free, instant and 100% client-side; decode calldata and bytes right in your browser.
Number Base Converter
Enter a number and pick its base to see it in binary, octal, decimal and hexadecimal at once, plus any custom base from 2 to 36. Conversions use BigInt, so even very large numbers stay exact.
Private by default: processing stays on your device
Example: 255 in every base
Input
255 (decimal)
Output
binary: 11111111 octal: 377 hex: ff
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Frequently asked questions
What bases are supported?
Any base from 2 to 36 in both directions. Binary, octal, decimal and hexadecimal are shown automatically, and the custom base field covers everything in between (digits 0-9 then a-z).
Does it handle very large numbers?
Yes. Conversions run on JavaScript BigInt, so there is no 2^53 precision limit. 40-digit numbers convert exactly. Negative numbers and a leading 0x/0o/0b prefix are accepted too.
Can I paste grouped digits like 1010_1010?
Yes. Spaces and underscores are ignored, so grouped binary or long hex values paste cleanly.
Is my input sent anywhere?
No. Every conversion happens locally in your browser; nothing is uploaded.
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