XML formatter / validator
Paste an XML file to indent it cleanly, minify it, or check that it is well formed — with the exact position of any error. It is handy for UBL invoices, RSS feeds and configuration files. The file is processed on your device, so a document you format never leaves your machine.
- 100% local
- Free · no account
- Instant result
This tool runs entirely in your browser — nothing is sent to a server.
XML is the lingua franca of structured documents — Peppol invoices, XRechnung, feeds, configuration files — but a file without indentation is an unreadable wall of text, and one missing quotation mark renders the whole document invalid. This tool validates your XML, locates the error (line and column) and reformats it with clean indentation — or minifies it to reduce its size.
Everything happens in your browser: you can process a complete invoice without it being transmitted anywhere.
How it works
Type the figures or drop the file you want to process — the tool checks them as you go.
Everything is computed directly in your browser. Nothing is sent to a server.
The result appears instantly, with the detailed breakdown ready to copy, download or keep.
Why use this tool
No account, no download, no limit: the result appears as soon as you enter your data.
Every rule, algorithm and check reflects what we use ourselves every day at Flexina.
The calculations follow the official standards, and the step-by-step detail lets you double-check the outcome.
What does running it locally bring you?
Files, figures and documents never leave your device: nothing is stored, nothing is sent.
Once the page is loaded, you can cut the network: the tool keeps working.
No upload, no account, no third-party server in between: results stay fast and fully private.
Frequently asked questions
Why is my XML invalid?
Classic causes: an unbalanced tag, a quotation mark missing from an attribute, a special character not escaped (&, <), or several root elements. The parser indicates the exact position of the first problem.
Format or minify, when to choose which?
Format to read, debug and compare two files; minify to transmit or store (removes spaces between tags, without changing the document).
Does my file leave my machine?
No, validation uses your browser’s parser, locally. Nothing is sent to a server.