Why do spaces become %20 or +?

In standard URI percent-encoding, spaces are encoded as `%20`. In `application/x-www-form-urlencoded` query strings, spaces can also be represented as `+`.

Updated: August 2026 • Verified v1.2

URL / URI Encoder

Developer ToolsEssential

Encode raw strings and query parameters into standard percent-encoded URLs (encodeURI & encodeURIComponent).

Local Browser Execution: Your input is processed locally in your browser and is not sent to UTL servers.

RFC 3986 Uniform Resource Identifier (URI): Percent-Encoding Specification

Understanding Your Results

Replaces non-alphanumeric and unsafe ASCII characters with a `%` followed by their hexadecimal ASCII/UTF-8 byte value (e.g. space becomes `%20`).

Practical Guidance & Next Steps

Use 'Component Mode' when encoding parameter values (e.g. a search query like `c++ & python`). Use 'Full URL Mode' when encoding an entire website address without breaking the protocol and domain.

What is this?

A standard URL percent-encoding tool that replaces unsafe ASCII and non-ASCII characters with `%XX` hex escape sequences for safe web transmission.

How does it work?

1. Paste your raw URL or query parameter string. 2. Choose 'Component Mode' (for parameter values like names, search queries) or 'Full URL Mode'. 3. Copy the encoded result.

Why use it?

Prevents broken links and server query parse errors when passing spaces, ampersands (`&`), question marks (`?`), and international characters into web URLs.

Technical Scope & Calculation Limitations

Component encoding encodes structural characters like `/` and `?`. Do not use Component Mode on full domain URLs.

Frequently Asked Questions

`encodeURI` preserves valid URL structural characters like `:`, `/`, `?`, and `#`. `encodeURIComponent` encodes everything except alphanumeric characters and `- _ . ! ~ * ' ()`.

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