Url Encode
Encode unsafe characters for use in URLs and query strings, or decode %xx escape sequences back to plain text. Uses the standard encodeURIComponent alphabet (A–Z a–z 0–9 and - _ . ! ~ * ' ( ) stay untouched) and flags malformed escapes when decoding.
TheCalculators — Url Encode
Printed thecalculators.com
Encoded Result
Hello%20World!%20search%3Fq%3Ddark%20mode%20%26%20coffee%3Dyes
62 characters
- Operation
- Encode
- Input Length
- 44 chars
- Output Length
- 62 chars
- Length Change
- +18
- Encoding Overhead
- 40.9%
- Non-ASCII Chars
- 0
How it works
- 1Safe alphabetencodeURIComponent leaves A–Z a–z 0–9 - _ . ! ~ * ' ( ) untouched
- 2Everything elseEach byte becomes %XX, where XX is its hex code — a space is %20, & is %26, = is %3D
- 3DecodingEach %XX is read back to its character; malformed sequences raise an error
Common escape reference
When decoding, "+" is treated as a space (the application/x-www-form-urlencoded convention). Reserve + literally as %2B when encoding.
Most useful next
Formula
encoded = text with every unsafe byte replaced by %XX (hex)
Pro tips
- • Encode query parameter values separately, then join them with & and =.
- • A very long encoded output usually means non-ASCII text — consider a shorter slug.
FAQ
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