URL Encoder / Decoder
Free URL encoder and decoder: component mode, whole-URL mode and form urlencoded mode, turning CJK and special characters into percent-encoding and back.
How to Use
- Choose a mode
Use Component for parameter values, Whole URL for a full address, and Form encoding for form posts.
- Type and read the result
Encoding happens as you type, with character counts and expansion shown alongside.
- Switch to Decode to reverse
Paste the encoded string and tick 'Treat + as space' for form data to restore the original.
FAQ
What is the difference between component and whole-URL encoding?
Component encoding escapes every special character including : / ? & = — use it for parameter values. Whole-URL encoding preserves those structural characters — use it for a complete address.
Why does Chinese text become a string of percent signs?
URLs may only contain ASCII, so non-ASCII characters are first converted to UTF-8 bytes and each byte is written as %XX — that is percent-encoding.
What does the plus sign mean in form encoding?
In application/x-www-form-urlencoded a space is encoded as + rather than %20. Tick 'Treat + as space' when decoding to restore it correctly.
Why did decoding fail?
Usually the string contains an invalid percent sequence such as %zz or a trailing lone %. Check that the original encoding is complete.