twineconvert

free · in-browser · no upload

YAML to TOML
Converter

Drop your YAML file. We'll convert it to TOML right here in your browser, your file never leaves your device.

or drop your file

Select your file here to get started

or drop your file here.

Accepts .yaml, .yml

nothing uploaded no file size cap no signup

How it works

Three steps. No upload, no signup.

  1. 1

    Drop your file

    Click the dropzone above or drag a YAML from your desktop. Files of any size, there's no upload, so there's no upload limit.

  2. 2

    Convert in your browser

    The conversion runs entirely in this tab using JavaScript and WebAssembly. Your file never touches our servers, we don't have any.

  3. 3

    Download

    Get your TOML the moment the conversion finishes. Convert another, or close the tab.

Files stay on your device

Your file is never uploaded. The entire conversion runs in your browser using WebAssembly. We can't see what you convert because we have no server to see it.

No file size limit

Server converters cap free users at 1-2 GB and gate larger files behind a paid plan. Since nothing uploads, our limit is whatever your browser can handle.

Free, no signup, no ads on conversions

No account required. No watermark on the output. No queue. Drop a file, get a converted file.

Why convert YAML → TOML

What this conversion is actually for

Migrating between config systems: from a YAML-heavy stack (Kubernetes, Ansible, GitHub Actions) to a TOML-based one (Cargo, Hugo, modern Python pyproject) means transcribing the same data. Doing it by hand is error-prone with deep nesting; an AST-aware converter handles the structural translation correctly.

A real example

You're rewriting a Hugo site config from `config.yaml` to `config.toml` (Hugo's preferred format since v0.110). Drop your YAML, get TOML out — every nested map and array survives the transformation.

Troubleshooting

YAML anchors and aliases didn't transfer.

YAML's `&anchor` / `*alias` features have no TOML equivalent (TOML has no reference mechanism). Our converter resolves anchors at parse time so the output TOML duplicates the value at every reference site. The data is preserved; the deduplication isn't.

Formats involved

About YAML and TOML

YAML, YAML Ain't Markup Language

YAML is a human-readable config format that's a strict superset of JSON. Used by Docker Compose, Kubernetes manifests, GitHub Actions workflows, Ansible playbooks, OpenAPI/Swagger specs, and CircleCI configs. Indentation matters, which trips up users accustomed to brace-based configs. Spec versions: 1.1 (2005, Ruby/Python ecosystems) and 1.2 (2009, current). Most tools default to a 1.1/1.2 hybrid.

How to open

Any text editor. VS Code, IntelliJ, and most modern IDEs ship YAML syntax highlighting and validation. The `yamllint` CLI catches indentation bugs before they reach CI.

Full YAML format guide →
TOML, Tom's Obvious Minimal Language

TOML is a config format designed by GitHub co-founder Tom Preston-Werner in 2013 as a more readable alternative to YAML and INI. Its appeal is unambiguous syntax — TOML files always parse the same way regardless of indentation. Used by Cargo (Rust), pyproject.toml (Python packaging), pnpm-workspace, Hugo, Netlify, and many others. v1.0.0 spec finalized in 2021.

How to open

Any text editor. Most modern IDEs ship TOML syntax highlighting; VS Code's Even Better TOML extension adds validation.

Full TOML format guide →

Related tools

Convert other files to TOML

Convert your YAML to other formats

FAQ

Common questions

Is this YAML → TOML converter really free?

Yes. No signup, no watermark, no daily file count limit. Every conversion runs in your browser, your file never touches our servers because there are no servers.

Where does my file go when I convert it?

Nowhere. The conversion runs entirely in your browser using JavaScript and WebAssembly. Your file is never uploaded to our servers. We don't have any servers handling files, there's nothing for us to log, store, or accidentally leak.

What's the maximum file size?

Whatever your browser can hold in memory. Practically, this means a few hundred MB on most computers, significantly larger than the 1-2 GB caps that server-upload converters charge for. Very large files (multi-GB) may require closing other browser tabs first.

Why convert YAML to TOML?

DevOps configuration (Kubernetes, Docker Compose, CI workflows). Application/package config in Rust, modern Python, and static site generators. The most common reason to convert is compatibility, TOML works in places where YAML doesn't, or vice versa.

How do I open a YAML file in the first place?

Any text editor. VS Code, IntelliJ, and most modern IDEs ship YAML syntax highlighting and validation. The `yamllint` CLI catches indentation bugs before they reach CI.

Does this work offline?

Once the page is loaded, the conversion itself runs entirely offline. The first time you use a tool, your browser downloads the conversion library (a one-time cache). If you reload while offline, the page won't load, but you can install the site as a Progressive Web App for full offline use.

Can I convert multiple files at once?

Single file at a time for now. Batch conversion is on the roadmap, for now, drop one file, download the result, then convert the next.