Number Base Converter
Free online number base converter. Convert between binary, octal, decimal, hex and any base 2-36: exact for huge numbers, 100% in your browser.
Hex ↔ String Converter
Convert UTF-8 text to a hex byte string and back. Handy for reading revert reasons, bytes32 values and calldata fragments. The 0x prefix is optional in both directions.
Private by default: processing stays on your device
Example
Input
Hello world
Output
0x48656c6c6f20776f726c64
These buttons share the page link, not your input.
Want to include your text?
Your current input will be stored in the link after the # symbol, not uploaded to HandyBrowserTools. Anyone with this link can read that text. If you send or post it, the service you choose also receives the link. Do not include passwords or private information.
Frequently asked questions
Why do I see an odd-length error when decoding?
Every byte is exactly two hex digits, so a valid hex string always has an even number of digits. An odd length means a digit was dropped somewhere, often a stripped leading zero.
Does it handle emoji and non-English text?
Yes. Text is encoded as UTF-8 before conversion, so multi-byte characters like emoji, accents and CJK scripts round-trip exactly.
How is this different from Base64?
Both represent bytes as text. Hex uses two characters per byte (larger but human-scannable and the convention on EVM chains); Base64 is more compact and common on the web. Use the Base64 tool for the latter.
Is anything sent to a server?
No. Conversion uses the browser's built-in TextEncoder and TextDecoder, so your data never leaves your device.
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