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URL Encoder

Encode and decode URL strings to proper percent-encoding format. Free online URL encoder for safe web addresses and query parameters.

URL Encoder is a free online developer tool that works right in your browser — whatever you enter is processed locally and never sent to a server. No installation, no signup; works on both phone and desktop, ready to use instantly.

Code tools designed for developers with syntax highlighting, real-time validation, and formatting. Full coverage of JSON, XML, YAML, SQL, and more.

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How to use

  1. 1 Open the URL Encoder tool page.
  2. 2 Paste your text, URL, or data into the input area.
  3. 3 Choose the operation mode and parameters.
  4. 4 Run the tool and review the result.
  5. 5 Copy or download the result.

Why we built this tool

As developers ourselves, we kept switching between scattered tools that sent our code to unknown servers. We built this developer suite so formatting, validation, and conversion all run locally — your code stays yours.

About URL Encoder: what you should know

Frontend developers building query strings, backend engineers constructing redirect URLs, and QA analysts crafting webhook POST bodies. URL encoding matters whenever slashes, spaces, ampersands, or non-ASCII characters appear in a parameter value — the wrong encoding breaks auth callbacks, tracking links, and form submissions.

Key features

  • Dual Mode: Percent & Plus Encoding — Standard percent encoding (RFC 3986) plus the `+` shortcut for form data (application/x-www-form-urlencoded). Toggle between them depending on whether you are building a REST query or a POST body.
  • Full Unicode Coverage — Chinese, Arabic, Cyrillic, and emoji characters are percent-encoded correctly instead of being silently dropped or causing a malformed URL. Paste a full internationalized query and verify the percent-UTF-8 output.
  • Quick URL Validation — Encoded results automatically get appended with the correct parameter prefix if you need a ready-to-paste `?param=value` or `&param=value` snippet.

Common use cases

  • Building OIDC Auth Callback URLs — OpenID Connect redirect URLs carry state and nonce parameters that must survive encoding. Encode your callback destination URL before inserting it into the authorization request — missed spaces in the redirect_uri are a common cause of auth failures.
  • Generating Trackable UTM Links — Marketing teams build UTM query strings that include campaign names, source identifiers, and sometimes Chinese characters or spaces. Proper encoding ensures tracking links open without parameter truncation.

Frequently Asked Questions

Is this tool free?

Yes, completely free with no signup required.

Can I use it on mobile?

Yes, it works on mobile browsers with touch support.

What category does this belong to?

Developer

Which programming language formats are supported?

Supports JSON, XML, YAML, SQL, CSV, TOML and more, plus code format conversion for Java, Python, TypeScript, etc.

What code and data formats are supported for formatting and validation?

ToolPure supports JSON, XML, YAML, TOML, CSV, SQL, and Markdown formatting. Validation includes syntax checking, schema validation for JSON, and well-formedness checking for XML.

Can I convert between different data formats?

Yes, you can convert between JSON, XML, YAML, CSV, and TOML. The converter preserves data types, nested structures, and array indices during conversion.

Is there a file size limit for code formatting?

Files up to 10MB can be formatted without issues. For larger files, the tools use Web Workers to prevent UI freezing. Syntax highlighting supports files with up to 100,000 lines.

Is URL Encoder safe? Is my data uploaded or stored?

Yes. URL Encoder is a pure front-end tool: whatever you type or paste is processed only in your browser's memory and never sent to a server. It disappears as soon as you refresh or close the page.

🔒 Privacy & Security：All processing happens locally in your browser. Files are never uploaded or stored.

🔒 Privacy: All processing happens locally in your browser. Your files and data never leave your device — no upload, no server, no tracking.

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