TL;DR: This is the entry point for three free XML tools that run entirely in your browser: an XML formatter, an XML validator and an XML minifier. Pick a tool below, or paste XML into the editor above and press Format XML — nothing is uploaded.
XML work tends to fall into three jobs: making a document readable, finding out why it will not parse, and making it smaller before it ships. Each job deserves its own page — a formatter has different advice from a validator, and a minifier has different caveats from both. This site is organised the same way: a starting point (this page) and three focused topic guides, one per job.
All three tools share one engine. That matters more than it sounds: the same parser powers the formatter, the validator and the minifier, so the error messages are identical, the line and column numbers always appear, and a document that validates here also formats and minifies cleanly. Nothing is uploaded, nothing is stored, and the tools keep working offline once the page has loaded.
Three XML tools, one place
XML Formatter
Pretty-print XML with 2-space, 4-space or tab indentation, with a syntax check before anything is re-indented. The main guide to the formatter topic.
Open XML Formatter →XML Validator
Check whether a document is well-formed and see the exact line, column and plain-English reason for every error, plus a structural report.
Open XML Validator →XML Minifier
Remove indentation and whitespace between tags, then compare the byte size before and after. Useful for builds and embedded XML.
Open XML Minifier →Which XML tool should I use?
| What you need | Use this tool | What you get |
|---|---|---|
| Make a minified or hand-edited XML file readable again | XML Formatter | Consistent indentation, normalised attribute spacing and a syntax check in one pass |
| Find out why a file will not parse | XML Validator | Line and column location, plain-English message, fix hint and a caret code frame |
| Shrink XML before packaging or sending it | XML Minifier | Compact output plus the exact bytes and percentage saved |
| Format XML on a machine where you cannot install anything | XML Formatter Online | The same formatter in a browser tab — no install, no admin rights, no upload |
| Validate against an XSD or DTD schema | A schema-aware validator (for example xmllint --schema) | This site checks well-formedness only; schema validation needs the schema document |
What all three tools have in common
- One parser, one error format. Every error reports a line, a column, a plain-English explanation and a fix hint — the same wording on every page.
- Content-preserving. Text, comments, CDATA sections and entity references are copied exactly; only indentation and attribute spacing change.
- Private by design. Formatting, validating and minifying run as JavaScript in your tab. There is no upload endpoint and no stored copy.
- A 2 MB cap. Oversized input is refused with a clear message so the page never freezes; larger files belong in xmllint or a desktop editor.
- Zero dependencies. No framework, no CDN, no external fonts — the whole toolset is a few local files.
How to use any of the tools
Paste your XML
Use the editor at the top of this page or open one of the three topic guides. The pane header shows the exact input size in bytes.
Pick the action
Format, minify or validate. The hub keeps the formatter available because it is the most common first step; the validator and minifier guides start on their own action.
Read the result or the errors
Valid XML appears in the right pane and can be copied with one click. Invalid XML is not changed at all — instead you get errors with line and column numbers.
Copy and move on
Copy result puts the output on your clipboard. Clear resets the editor and Load sample fills in a small document if you are just testing.
How this site is organised
This page is an overview, not a keyword page: it exists to route you to the right tool. Each of the three jobs has its own topic guide with the full explanation, examples and FAQ — XML Formatter for pretty-printing, XML Validator for well-formedness checks and XML Minifier for whitespace removal. The XML Formatter Online page is a focused version of the formatter guide for browser-only workflows.
If you only remember one thing: paste the XML, run the check, read the line and column. Everything else on this site exists to explain that loop.
Frequently asked questions
Which XML tool should I start with?
Start with the XML Formatter when you want readable, consistently indented output. If the file will not parse at all, go straight to the XML Validator, which reports the line and column of every error. If you need a smaller file, use the XML Minifier. All three share the same parser, so the error messages are the same everywhere.
Are these XML tools free?
Yes. Every tool on this site is free, has no account requirement, no usage limit and no paid tier. There is no advertising inside the editors and no upload.
Is my XML uploaded to a server?
No. Formatting, validating and minifying are implemented in plain JavaScript that runs in your browser. You can open the browser's developer tools, switch to the Network tab and run any action: no request carries your document.
Do the tools work on mobile?
Yes. The editor and result panes stack on narrow screens and all processing happens on the device. Mobile keyboards make very long documents awkward, so phones are best for short responses or configuration blocks.
Can I use the tools offline?
Once the page and its local assets have loaded, all three tools keep working without a network connection, because using them makes no requests.
Do the tools validate XML against an XSD or DTD schema?
No. They check well-formedness: tag nesting, attribute quoting, entity references and a single root element. Schema validation needs the schema document and a schema-aware validator such as xmllint --schema.