XML URL Encoder

Confirms your XML is well-formed, then percent-encodes it with encodeURIComponent so it's safe to use as a URL query string value, useful for passing an XML payload through a GET request or a redirect link. A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-23

Overview

Introduction

URLs can't safely carry raw XML: angle brackets, quotes, ampersands, and spaces all have special meaning or aren't allowed unescaped in a query string. This tool validates your XML, then percent-encodes it so it survives being passed as a URL parameter intact.

It's the tool to reach for when a small XML payload needs to travel through a GET request, a redirect link, or any other place URL syntax rules apply.

What Is XML URL Encoder?

A URL encoder specifically for XML: it first checks that your input is well-formed XML (the same check the XML Validator performs), then percent-encodes the text using the standard encodeURIComponent behavior.

The result replaces every character outside a small safe set (letters, digits, and - _ . ! ~ * ' ( )) with its %XX percent-encoded byte representation, matching what browsers do when encoding a query string value.

How XML URL Encoder Works

Your input is parsed with the same well-formedness check used across this category's tools; any syntax error is reported before encoding proceeds.

Once validated, the original text is run through JavaScript's built-in encodeURIComponent, producing a string safe to embed as a single query string value.

When To Use XML URL Encoder

Use it when you need to pass an XML payload through a URL, a GET request parameter, a redirect target, a bookmarklet, without it being mangled or truncated by URL syntax.

It's also useful for constructing a test URL by hand when debugging an API or webhook that accepts XML via a query parameter.

Features

Advantages

  • Runs entirely client-side, so XML with real configuration data never leaves your browser.
  • Validates the document is well-formed before encoding, catching a mistaken input before you embed it in a URL.
  • Uses the same encoding behavior browsers use for query string values, so results match what a real request would produce.
  • No size limit beyond what your browser can hold in memory (though very large payloads make poor URL parameters regardless).

Limitations

  • Only validates well-formedness, not schema conformance, before encoding.
  • Very large XML documents make impractical URL parameters even after encoding; most servers and browsers cap total URL length.
  • Doesn't encode a full URL, only a component value, don't use it to encode an entire URL including its scheme and host.

Examples

Encoding a small XML document

Input

<a>1</a>

Output

%3Ca%3E1%3C%2Fa%3E

Angle brackets and the forward slash are percent-encoded; letters and digits are left as-is.

An unclosed tag is caught before encoding

Invalid input

<a>1</b>

Parser error

Expected closing tag </a> but found </b>

Validation runs first, so malformed input is never silently encoded.

Corrected version

<a>1</a>

Best Practices & Notes

Best Practices

  • Use this for genuinely small XML fragments; large payloads belong in a request body, not a URL.
  • Decode with the XML URL Decoder (or any standard URL decoder) to confirm the round trip before relying on it in production.
  • Check your server or framework's URL length limits before assuming an encoded payload will fit.

Developer Notes

`urlEncodeXml` (in this category's `lib/url-encode-xml.ts`) validates with `parseXmlDocument` from `xml-core.ts`, then encodes the original input text (not a reformatted version) with the standard `encodeURIComponent`. Whitespace and formatting from the original input are preserved exactly, only characters outside the unreserved set are transformed.

XML URL Encoder Use Cases

  • Passing a small XML payload as a GET request query parameter
  • Constructing a redirect URL that carries XML state
  • Building a test URL by hand while debugging an API that accepts XML via a query string
  • Embedding an XML fragment in a bookmarklet or browser extension URL

Common Mistakes

  • Encoding a large XML document and expecting it to work reliably as a URL parameter; most servers cap URL length.
  • Using this to encode an entire URL (including scheme and host) rather than a single component value.
  • Encoding malformed XML by accident, this tool validates first specifically to prevent that.

Tips

  • Use the XML URL Decoder to verify the round trip decodes back to your original document.
  • Pair with the XML Minifier first if you want the smallest possible encoded payload.
  • Upload a .xml file directly instead of copy-pasting if the document is large.

References

Frequently Asked Questions