TOML to YAML Converter
FileFlip converts TOML to YAML entirely inside your browser, using the text engine compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert a TOML file to YAML?#
- Drop your TOML file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to YAML and the conversion starts on its own. FileFlip downloads nothing at all, because everything it needs is already built into your browser, then runs the text engine on your own machine.
- Save the YAML file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting TOML to YAML lose quality?#
No. Converting TOML to YAML writes the data out again without discarding any of it, so nothing that was in the TOML file is lost on the way. What changes is the size of the file, not what is inside it.
Is it safe to convert TOML files online?#
Yes, because nothing is uploaded. FileFlip converts TOML files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What TOML to YAML actually does to the file#
Converting TOML to YAML runs on the text engine, downloads nothing at all, because everything it needs is already built into your browser, writes the data out again without discarding any of it, keeps value types, and drops comments.
| Engine | the text engine |
|---|---|
| Conversion path | One step: TOML → YAML |
| Downloaded to your browser | Nothing. Your browser already has everything this conversion needs |
| Quality | Lossless |
| You get back | One file |
| Where it runs | On the page's own thread, so a very large file will make the tab wait |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Comments | Dropped | The target format has nowhere to put it. |
| Value types | Kept | Carried through into the converted file. |
Worth knowing before you start:
- this conversion runs on the page's own thread, so a large file will freeze the tab while it works
What is a TOML file?#
A TOML file holds configuration as key-value pairs grouped into tables, with native types for strings, integers, floats, booleans, arrays and dates.
Pick TOML for configuration files a person writes and re-reads by hand, where explicit types and unambiguous structure matter more than deep nesting.
Convert TOML to JSON or YAML when the data needs to nest more than a couple of levels deep, or when the tool consuming it doesn't have a TOML parser.
What is a YAML file?#
A YAML file holds structured data written with indentation instead of brackets, extending JSON's data model with comments, references and multi-line strings meant to be edited by a person.
Choose YAML for configuration a person edits by hand and wants to comment, like CI pipelines or Kubernetes manifests.
Convert YAML to JSON when a program needs to consume the file and comments and anchors aren't needed, since most JSON libraries won't read YAML directly.
TOML to YAML questions people ask#
Does TOML support comments?
Yes. TOML comments start with a hash character and run to the end of the line, the same as YAML and Python. That's one of the reasons TOML was picked for Cargo.toml and pyproject.toml over JSON, which has no comment syntax at all.
Why can't I convert a TOML file to a JSON array?
A TOML document always starts as a table of key-value pairs, so a file that only needs to model a top-level list, like a plain array of strings, doesn't fit TOML's grammar at all. Converting a JSON array to TOML has to wrap the array under a key, like items = [...], because TOML has no bare top-level list.
What happens to TOML's dates when converting to JSON?
TOML has a native date-time type with its own syntax, and JSON has none, so converting to JSON turns every TOML date into a plain string. Which string format it becomes depends on the converter, since JSON doesn't specify one either.
Why does YAML turn NO into false?
YAML's core schema treats a set of unquoted words, including no, off and n, as boolean false, and yes, on and y as true. This is called the Norway problem because a two-letter country code or an abbreviation typed without quotes gets silently converted to a boolean. Wrapping the value in quotes, so it reads as the string NO rather than the word no, avoids it.