Does this check my XML against a schema?

No. This is a well-formedness check only. Schema validation needs the DTD or XSD that describes what the document is supposed to contain, and there's no way to guess that from the document itself. Well-formedness is what you need when a parser refuses the file outright.

Why does one missing tag produce several errors?

Because everything after it is nested one level deeper than the parser thinks. A missing ` ` makes the next legitimate close look mismatched, and the one after that, and so on. Always fix the first error reported and re-check rather than working through the list.

Are XML tag names case sensitive?

Yes, unlike HTML. ` ` and ` ` are different elements, so ` text ` is not well-formed. It is one of the most common errors in hand-edited XML and this tool reports it explicitly rather than as a generic parse failure.

XML Validator

Check whether an XML document is well-formed and, when it isn't, find the tag responsible. Every error names both ends of the problem — the tag that was expected, the tag that was found, and the line each of them is on — because an unclosed element three hundred lines up is what actually causes an error reported at the bottom of the file. It also counts what's in the document, so a valid result tells you something rather than nothing.

Your text

Result

Nothing is uploaded — this tool runs inside your browser, so your files never leave your device.

Help us improve

Why use this tool

Finds unclosed tags, mismatched closes and more than one root element
Reports the line and column of both the error and the tag that opened it
Counts how many elements are still open, so you know the scale of the problem
Runs in your browser — no upload, no size limit but your own machine

How it works

1Paste the XML you want checked.
2Read the error — it names the tag expected, the tag found, and where each is.
3Fix the first error and check again; one missing tag often reports as several.

XML Validator — frequently asked questions

It is the minimum bar for XML: every element closed, closed in the right order, one root element, and attributes properly quoted. A document that isn't well-formed can't be parsed at all. It's a separate question from validity against a DTD or XSD schema, which asks whether the right elements are in the right places.

More developer tools

Text → Base64 Base64 → Text URL Encoder URL Decoder JSON Formatter JSON Minifier

Looking for something else? Browse all developer tools

Explore the other tools

Same deal everywhere on the site — free, no sign-up, and no watermark on anything you download.

QR Code Tools Barcode Tools PDF Tools Image Tools SEO Tools Text Tools Calculators Unit Converters Color Tools File Tools Business Tools AI Tools Utilities

Or see every tool on one page.