URL Encoder & Decoder – Percent-Encode Links and Parameters

URLs are only allowed a small cast of characters, yet real links need to carry search phrases with spaces, names with accents, and values containing &, = and ?. Percent-encoding is the system that makes it work: unsafe characters are replaced by a % followed by two hex digits (%20 for a space, %C3%A9 for é). This tool encodes text ready for a URL and decodes encoded URLs back into readable form, with two modes — component mode for a single query value (the strict, common case) and full-URL mode that preserves the structural characters of a complete link. It is the quick fix for broken links, mangled parameters and unreadable analytics URLs.

Quick Answer: Paste text to percent-encode it for a URL, or paste an encoded URL to decode it — with component and full-URL modes.

Free Online Tool

URL Encoder / Decoder

Make links safe to travel, and read the ones that arrive encoded.

Direction

Mode

Input

Output

How to Use the URL Encoder / Decoder

Choose Encode or Decode.
Pick the mode: Component for one value (a search term, a parameter), Full URL for a whole link.
Paste your text and press Convert.
Check the output: encoded text shows %XX escapes; decoded text should read naturally.
Copy the result into your link, redirect or code.

Key Features

Encode and decode in both component and full-URL modes.
Correct UTF-8 percent-encoding for accented and non-Latin text.
Decodes + as space in component mode, matching form-data conventions.
Instant conversion with one-click copy.
Runs locally — decode private tracking links safely.

Best Practices and Tips

Encode values, not whole URLs: encode each query value separately, or the & and = that structure the URL get encoded too and the link breaks.
A space becomes %20 in a path but often + in form-submitted query strings; both are understood, but %20 is always safe.
Double-encoded text (%2520) means something encoded an already-encoded value — decode once more and find the culprit upstream.
Browsers display many URLs decoded in the address bar but send them encoded — copy from the page source or analytics for the true string.
Redirect chains and UTM links are far easier to debug once decoded into readable text.

Common Mistakes to Avoid

Encoding a complete URL in component mode, destroying its structure and producing a single unreadable blob.
Assuming + always means a literal plus; in query strings it usually means a space, and a real plus must arrive as %2B.
Decoding text that was never encoded and contains % by chance (like ‘50% off’), which can throw errors — the tool reports these.
Building links by hand with raw spaces or accents and hoping browsers cope; some do, many downstream systems do not.

Frequently Asked Questions

What is percent-encoding?

It is the URL standard for representing unsafe characters: a percent sign followed by the character’s byte value in hexadecimal. A space is byte 32, written %20. Non-ASCII characters are first converted to UTF-8 bytes, and each byte gets its own %XX escape.

Component mode or full-URL mode — which do I need?

Component (encodeURIComponent) escapes nearly everything except letters, digits and a few marks — right for encoding a single value going into a URL. Full-URL mode (encodeURI) leaves : / ? & = and other structural characters alone — right for encoding a whole link that has spaces or accents in it.

Why did decoding fail with a URIError?

The input probably was not valid percent-encoding: a lone % not followed by two hex digits, or escapes forming invalid UTF-8. Real-world culprits include truncated links and text with a literal % sign. The error means ‘this was not properly encoded’, which is itself useful information.

Does decoding change + signs?

In component mode, yes: following form conventions, + decodes to a space, because that is how browsers submit form data. In a pasted full URL path, a + may be literal — if your decoded text looks wrong around plus signs, that is why.

Is this the same as Base64?

No. Base64 re-encodes entire data into a different alphabet; percent-encoding only escapes the unsafe characters inside a URL and leaves the rest readable. Links usually need percent-encoding; data payloads use Base64.