Input
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How to use
- Enter or paste the text you want to encode.
- Choose letter case, a byte separator and an optional 0x prefix.
- Copy the Hex string or download the complete JSON result.
Text to Hex Converter
A Hex string is a readable spelling of encoded bytes. This tool first encodes your text as UTF-8, then writes every byte as exactly two hexadecimal digits.
ASCII letters use one UTF-8 byte each. Chinese characters and emoji use several bytes, so one visible character can produce several pairs of hex digits.
Representations and workflow
String conversion is different from numeric conversion. The text "123" becomes 313233 because the characters 1, 2 and 3 have byte values 31, 32 and 33 in hex. The number 123 becomes 7b in a number-base converter.
Hello 中文 👋48656c6c6f20e4b8ade6968720f09f918bEach pair is one UTF-8 byte; a character may need more than one pair.
Precision and validation
The default output is lowercase with no separator. Spaces or new lines change only the display, not the encoded bytes. The optional 0x appears once at the start of the result. Every byte retains its leading zero if needed.
Interpreting and reusing the result
Text is not normalized or converted to a different case before encoding. Actual spaces, line endings, a UTF-8 BOM and control characters remain part of the byte stream. Unpaired Unicode surrogates produce an 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 ordinary letters and numeric strings?
Yes. For example, abc becomes 616263, ABC becomes 414243, and the string 123 becomes 313233. Numeric base conversion is a different operation.
Does this support Chinese and emoji?
Yes. UTF-8 encodes Unicode characters into one or more bytes. For example, 中文 becomes e4b8ade69687.
Do spaces or uppercase letters change the bytes?
No. Letter case and output separators change only the Hex notation. Spaces in the original text are actual bytes and are encoded.
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 displayed string. Download JSON includes the full result and byte count, preserving Unicode and control characters.