📌 Use Cases

URL encoding (percent-encoding) is used to safely transmit special characters in web addresses. This tool converts between encodeURI and encodeURIComponent, helping developers correctly handle Chinese parameters, spaces, and symbols, avoid 400 errors, and is ideal for front-end link building and debugging query strings.

📖 Learn More About url encoder

Why You Need It

Put special characters (spaces, Chinese, symbols) into a URL safely.
Build query strings that won't 400 on the server.
Debug encode/decode mismatches in front-end code.

How It Works

Percent-encoding replaces unsafe characters with %HH byte sequences. encodeURI leaves path characters alone; encodeURIComponent encodes everything, which is what you want for query values.

A Quick Example

Paste a search term with spaces and Chinese, switch between the two modes, and copy the safe URL.

Common Mistakes

Using encodeURI on a full query value (leaves & = ? unsafe).
Double-encoding already-encoded strings.
Forgetting to decode before display.

About the free online URL Encoder / Decoder

Looking for a free online URL Encoder / Decoder? URL encoding (percent-encoding) is used to safely transmit special characters in web addresses. This tool converts between encodeURI and encodeURIComponent, helping developers correctly handle Chinese parameters, spaces, and symbols, avoid 400 errors, and is ideal for front-end link building and debugging query strings. This tool is completely free and requires no registration — every operation runs locally in your browser, your data is never uploaded to any server, and you can use it anytime just by opening the page.

🔗 URL Encoder / Decoder

Encode URLs to percent-encoded format or decode them back to readable text. Supports both encodeURI and encodeURIComponent modes.

Mode

Encoding Method

Input Text

Result

🔒 All processing happens in your browser. No data is uploaded to any server.

📋 How to Use

Select the mode: "Encode" (text to URL-encoded) or "Decode" (URL-encoded to text).
When encoding, choose the method: encodeURIComponent for query parameters or encodeURI for full URLs.
Type or paste your text into the input box.
Click "Encode" or "Decode" to process, or use "Swap" to flip input and output.
Click "Copy Result" to copy the output to your clipboard.

❓ FAQ

What is URL encoding?

URL encoding (also called percent encoding) converts characters that are not allowed in a URL — such as spaces, special symbols, and non-ASCII characters — into a format that can be safely transmitted. Each unsafe character is replaced with a percent sign followed by two hexadecimal digits, e.g. a space becomes %20.

Why do I need to encode URLs?

URLs can only contain a limited set of ASCII characters. Characters like spaces, &, =, ?, and non-English letters must be encoded to avoid ambiguity and ensure the URL is interpreted correctly by servers, browsers, and APIs. Without encoding, special characters could break the URL structure or alter its meaning.

What is the difference between encodeURI and encodeURIComponent?

encodeURI is designed for encoding a complete URL. It preserves characters that have special meaning in a URL — such as : / ? # & = + — so the URL structure stays intact. encodeURIComponent is meant for encoding individual query parameter values. It encodes all reserved characters, ensuring the value can be safely embedded in a query string. Use encodeURI for full URLs and encodeURIComponent for parameter values.

💡 Use Cases

🌐

Query Parameters

Safely embed user input or special characters in URL query strings.

🔌

API Requests

Encode parameters for REST API calls that accept URLs or special text.

🐛

Debugging

Decode encoded URLs to inspect the actual parameter values being sent.

🔗 Related Tools

📚 Further Reading

Want to go deeper? These tutorials pair well with this tool.

📄How URL Encoding Works: Why Chinese Characters Become %E4%... 📄10 Online Tools Every Developer Should Bookmark 📄JSON Formatting & Validation: 5 Tips Every Developer Needs

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