Converting XLS to YAML gives you the same content in a different container. It runs in your browser: nothing is uploaded, there is no queue and no size limit.
What changes when you convert XLS to YAML
- Both formats are lossless: nothing in the picture or sound changes, only the container and the compression.
- Each row becomes one record with the header row as keys. Numbers stay numbers, empty cells become null.
When to convert, and when not to
Convert to YAML for configuration files. Human-friendly configuration. Indentation instead of braces.
Keep XLS for nothing new, so convert it. The old binary Excel format.
How to convert XLS to YAML
- Drop your XLS file on the converter above, or click to choose. Several at once is fine.
- Check the options if you need them: sheet name (blank = first).
- Click Convert, then Download. Nothing was sent anywhere, your browser did the work.
Questions
Is my XLS file uploaded?
No. The conversion runs in your browser with WebAssembly. There is no upload endpoint on this site. You can open your browser's Network tab, or go offline after the page loads, and it still works.
Is there a file size limit?
No fixed one. The limit is your device's memory: a large data file on a phone is slower than on a laptop, but nothing is rejected for being big.
Is it free?
Yes, without an account, without a daily cap and without a watermark. Your device does the computing, so there is no server bill to pass on.
Will the quality drop?
No. YAML is lossless: the data content is stored exactly.
Can I convert several files at once?
Yes. Drop them all; each is converted in turn and you can download them one by one or as a single ZIP.
Which engine does the conversion?
Data engine (SheetJS, js-yaml, fast-xml-parser, smol-toml), compiled to WebAssembly and running in your browser. First use downloads about 0.9 MB, cached afterwards.