Free JSON to YAML Converter, No Sign-up and No Upload
This free JSON to YAML converter rewrites JSON as indented YAML. There is no sign-up or login, no watermark, and no upload: your file is converted in your browser and never leaves your device.
YAML is easier for people to read and edit, which is why it is common in Docker Compose, Kubernetes and CI configuration. If a tool gives you JSON and your project expects YAML, this does the rewrite in one step.
- Free
- No sign-up
- Never uploaded
- No watermark
Your files are converted on your device and never uploaded.
How to convert
- Drag your JSON files onto the page or choose them with the file picker.
- Pick YAML as the target format.
- Check the options, then start the conversion.
- Download each YAML file, or take a batch as one ZIP.
Features
- Runs natively in your browser with no engine download.
- Produces indentation-based, readable YAML.
- Suited to config files for containers and CI tools.
- Batch conversion of several files.
- No watermark and no account.
Supported formats
About the formats
JSON versus YAML
JSON is strict about quotes, braces and commas, which makes it easy for programs to parse. YAML uses indentation instead and is easier on the eye. YAML is generally described as a superset of JSON, so the same data can be written in either form.
YAML allows comments, which JSON does not, but comments in your own files are only something you can add after converting.
Privacy: how it works
- Your JSON files stay on your device. The page reads each file with the browser's file API, converts it with code running in the tab, and hands the result back as a download. No upload happens, so there is no copy of your file on our servers to protect, delete or leak.
- There is nothing to sign up for and no login. The converter does not ask for an email address, and it does not need to know who you are to do its job.
- You can check the claim yourself: open your browser developer tools, watch the Network tab while a file converts, and you will see no request that carries your file.
- Config files can contain hostnames, keys and other secrets. They are handled only in your browser tab and are never sent to a server.
Tips
- Review the output once before committing it, since indentation carries the structure in YAML.
- Use spaces, not tabs, when you edit the result by hand.
- Add comments to the YAML afterwards to document settings.
- Quote values that look like other types, such as yes, no or version numbers, if your tool reads them literally.
- Convert back with the YAML to JSON converter to check that the data round-trips.
Frequently asked questions
Is it really free?
Yes. There is no price, no trial, no credit card and no watermark added to your results. Ulkaa Tool does the conversion with your own device, so there is no server bill to pass on to you.
Are my files uploaded?
No. Your JSON files are read and converted inside your browser and are never sent to Ulkaa or to anyone else. The result is created on your device and you save it from there.
Do I need an account?
No. There is no sign-up and no login. Open the page, add your files and convert. An Ulkaa account is not needed for anything on this tool.
Is there a file size limit?
No limit is set by us. The real limit is your device: the conversion uses your own memory and processor, so very large files can be slow, and a very big batch may need to be split into smaller runs.