Convert YAML to CSV

Convert YAML to CSV in your browser: load your YAML, choose CSV as the target, and download the result. The converter reports exactly what it could not carry across, and nothing is uploaded to a server.

Convert YAML to CSVRuns in your browser. Nothing uploaded.

When you need this

A YAML file holding a list of records — test fixtures, seed data, an inventory, a list of environments — becomes something you can sort, filter, pivot, or hand to someone who works in a spreadsheet.

How to convert YAML to CSV

Load your YAML: Drag the .yaml or .yml file in from the repository you are working in. Indentation is preserved exactly as written, so a paste from a terminal works too. Nothing leaves your browser at this or any later step.
Choose the target format: Press Ctrl+Shift+K (Cmd+Shift+K on a Mac) to open the conversion panel, then pick CSV as the target. The source and the result sit side by side.
Read the loss report: The panel shows whether the conversion is lossless for your particular data, and lists every value it had to transform. Adjust indentation, key sorting and null handling if you need to.
Take the CSV: Download the .csv file, copy it, or open it as a new tab to keep working on it in the CSV views.

What survives the conversion

YAML to CSV cannot be lossless, because the two formats express different things. Only a sequence of flat mappings converts cleanly.

Only a sequence of flat mappings at the root converts cleanly. A mapping at the root describes one thing, not a list of things, and has no rows.
Anchors are expanded first, so a record that inherited from a shared block comes out with those columns filled in rather than empty.
Nested mappings inside a record are serialised into the cell, because a CSV cell holds one value.

A worked example

A sequence of mappings becoming rows:

- env: prod
  replicas: 3
- env: staging
  replicas: 1

YAML in

env,replicas
prod,3
staging,1

CSV out

Privacy

The conversion runs in your browser — in a Web Worker for anything above a quarter of a megabyte, so the page stays responsive. Your data is not uploaded, not logged and not stored. There is no account, and the whole thing works offline.

Convert YAML to CSV

Questions

My YAML is a mapping, not a list. Why is there no table?

Because a mapping at the root is a single record, and a CSV of one row with a column per key is almost never what you wanted. Wrap it in a sequence — a single - in front of the first key — if a one-row table is genuinely the goal.

Is converting YAML to CSV lossless?

No, and no tool can make it so. Only a sequence of flat mappings converts cleanly. The converter lists every affected value rather than silently dropping it.

Is my YAML uploaded to a server?

No. The file is read and converted by your browser. Nothing about its contents is sent anywhere, which you can verify in your browser’s network panel or by using the tool with the network disconnected.