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URL Encoder / Decoder

Percent-encode text for URLs, or decode it back.

Complete Guide

About the URL Encoder & Decoder

URLs have a small vocabulary they are allowed to speak, and everything else must be spelled out in percent escapes. This encoder applies the same percent-encoding rules browsers use for URI components, turning spaces, ampersands, and non-Latin characters into forms any server will parse correctly. Flip to Decode to make escaped strings readable again — invalid escapes produce a clear error rather than silent corruption. Everything runs client-side; nothing you paste goes over the network.

Which characters actually need escaping

A URL reserves a handful of characters for structure: ? starts the query, & separates parameters, = joins keys to values, # begins fragments, and spaces simply are not allowed at all. Drop any of these unencoded into a parameter value and the receiving server misreads where your value ends. Percent-encoding replaces each offender with % followed by its hexadecimal byte value — a space becomes %20, an ampersand becomes %26 — so the character travels as data rather than being mistaken for syntax.

Encode components, not whole URLs

This tool encodes the way component-style functions such as encodeURIComponent do: nearly every reserved character gets escaped, because inside a single parameter value those characters ARE data. That is correct for query-string values and wrong for a complete address — encode https://example.com/path wholesale and the scheme's colon and slashes get escaped too, leaving a mangled string. The rule of thumb: build the URL first, then percent-encode only the individual pieces you insert into it. Letters, digits, and the marks - _ . ! ~ * ' ( ) pass through untouched.

The space problem: %20 versus +

You will meet both conventions in the wild, and they come from different specifications. Proper percent-encoding writes a space as %20. An older convention from HTML form submissions writes it as +. Most servers treat the two interchangeably inside query strings, but some treat a literal + as a plus sign — which means data you intended as a+b can arrive decoded as 'a b'. When interoperability matters, %20 is the unambiguous choice, and it is what this tool produces. If a decoded string unexpectedly contains plus signs where spaces should be, run the decode again treating plus as space.

Unicode and edge cases

Characters outside ASCII — Hindi, emoji, accented Latin — are first converted to UTF-8 bytes, then each byte is percent-encoded individually, which is why a single emoji can expand into several %XX sequences. On the way back, a % that is not followed by two hex digits is invalid encoding; rather than guessing, the decoder reports the error so you can fix the input instead of shipping corrupted data downstream.

Video slot: url-encoder-walkthrough.mp4

Encoding a search query containing spaces, ampersands, and emoji, then decoding a tracking URL back into readable form.

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Simple Step-by-Step Guide

How to Use URL Encoder & Decoder Online

Follow these simple steps to use URL Encoder & Decoder securely in your web browser.

  1. 1

    Select Action Mode

    Choose Encode to escape special characters or Decode to restore human-readable text.

    01-url-encoder-select-action-mode.png

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  2. 2

    Enter URL or String

    Type or paste your URL or query string parameter into the box.

    02-url-encoder-enter-url-or-string.png

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  3. 3

    Copy and Save String

    Click copy to save the RFC 3986 percent-encoded output to your clipboard.

    03-url-encoder-copy-and-save-string.png

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Technical Specs

Features & Specifications

Standard

RFC 3986 Uniform Resource Identifier

Engine

encodeURIComponent / decodeURIComponent

Privacy Status

100% In-Browser Local Processing

100% Free & Private In-Browser Processing

Rupix operates on a zero-upload architecture. All computations, file parsing, and transformations occur locally inside your web browser. No document bytes, sensitive text, or personal data are ever uploaded or transmitted to remote servers.

Highlights

Why use Rupix URL Encoder & Decoder?

RFC 3986 Standard

Encodes reserved characters into percent-encoded hex sequences.

Bidirectional Converter

Easily switch between encoding query parameters and decoding encoded URLs.

Full Unicode Support

Safely handles non-ASCII characters and UTF-8 multi-byte sequences.

Q&A

Frequently Asked Questions

A mechanism for representing characters inside URIs where special characters like spaces and slashes are replaced by % followed by two hex digits.
Certain characters are reserved for URI structure; leaving them unencoded inside values causes routing and parsing errors on the server.
Letters, digits, and - _ . ! ~ * ' ( ) pass through unchanged; component-style encoding escapes everything else.
Just the values. Encoding a full URL also escapes its structural colon, slashes, and ampersands, breaking it — unless the entire address is itself a parameter value.
%20 under standard percent-encoding, which is what this tool emits. Plus-as-space is a separate HTML form convention that some servers apply and others do not, so %20 is the safer default.
Yes. They are converted to UTF-8 first, so one character may become several consecutive %XX sequences — that is expected behavior.
A % sign not followed by two hexadecimal digits forms an invalid escape. The decoder rejects it outright instead of silently producing wrong output.
It happens when already-encoded text gets encoded again — a space becomes %2520 because %25 is itself the escape for %. Just run Decode twice; if the result looks half-readable, another pass finishes the job.
No. All encoding and decoding executes strictly in your local browser memory.