Encode Query String Parameters
Percent-encode query parameter values before building a URL. Avoid broken requests caused by spaces, ampersands and Unicode.
Part of the free URL Encoder. Runs in your browser — nothing is uploaded.
Encode Query String Parameters
Build query strings by encoding each value, then concatenating key=value pairs. Encoding the whole string at once will also encode the & and = that hold it together.
Worked example: A search query value
Raw value
q=css grid & flexbox
Safe query pair
q=css%20grid%20%26%20flexbox
Practical tip
In JavaScript, URLSearchParams encodes values for you. In other languages, use the equivalent of encodeURIComponent on each value.
How to use this URL Encoder
- 1Use the live tool above — it runs entirely in your browser and never uploads your data.
- 2Paste the sample from the worked example, or use your own input.
- 3Copy the result, then adapt the same steps in your editor, script, or pipeline.
Encode Query String Parameters FAQs
Should I encode the parameter name too?
Yes if the name can contain reserved characters. Most names are plain tokens and do not need it.
How do I encode an array of values?
Repeat the key (colors=red&colors=blue) or use a convention such as colors[]=red. Encode each value either way.
More URL Encoder pages
- URL Encode Spaces to %20Turn spaces into %20 with encodeURIComponent. See the difference between %20 and +, and encode any string online.
- encodeURIComponent OnlineRun encodeURIComponent in the browser. Encode query values, JSON snippets and reserved characters exactly as JavaScript does.
- URL Encode Special CharactersPercent-encode &, =, ?, # and / so they can sit safely inside a query value. Free online URL encoder.
- URL Encode UTF-8 and UnicodePercent-encode accents, non-Latin letters and emoji as UTF-8 bytes. See why café becomes caf%C3%A9.
- HTML Form URL Encoding (Spaces as +)Encode text the way HTML forms do: spaces become +, and other reserved characters become %HH. application/x-www-form-urlencoded.
- encodeURI vs encodeURIComponentSee the difference between encodeURI and encodeURIComponent on the same URL. Learn which one belongs in query values.
- Bulk URL EncoderURL-encode many lines at once. Paste a list of values or URLs and encode each line independently.
- Encode a URL for an API RequestPercent-encode path and query values before calling an API. Avoid 400s caused by spaces, Unicode and reserved characters.
- URL Encode & and =Encode & as %26 and = as %3D so they can appear inside a single query value without breaking the string.