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OpenAPI Bundle Downloader

Turn a multi-file OpenAPI spec into one single file. We fetch every external $ref and put its content in place. Download as JSON or YAML.

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What is the OpenAPI Bundle Downloader?

Large API specs are often split into many files. The main file uses $ref links like ./schemas/user.yaml to point to other files. Many tools, like code generators and some gateways, need everything in one file.

This tool downloads the main spec, follows every external $ref (up to 60 files), and places the content right where it is used. Internal links like #/components/schemas/User are kept as they are. Circular references are left as links and reported, so nothing breaks.

How to use it

  1. Paste the link to the main OpenAPI file (JSON or YAML).
  2. Press Bundle spec.
  3. Read the note to see how many external refs were bundled.
  4. Download the single file as JSON or YAML.

Why people like this tool

Resolves external refs

Relative and full URL $refs, in JSON or YAML files.

Keeps internal refs

#/components links stay small and clean.

Safe with loops

Circular refs are detected and left as links.

Two formats

Save the bundled spec as JSON or YAML.

How it works, in one picture

Infographic: how to use the OpenAPI Bundle Downloader in 4 easy steps: Paste the link, Run the tool, Check the result and Save your file. You get: Resolves external refs, Keeps internal refs, Safe with loops and Two formats.

Frequently asked questions

What is a $ref?
It is a pointer to another part of the spec, in the same file or another file. Bundling copies that part into the main file.
Is bundling the same as dereferencing?
Not quite. Full dereferencing also replaces internal refs, which can make the file huge. We only inline external files, which is what most tools need.
Can the referenced files be on another server?
Yes, as long as they are public. We fetch up to 60 files.

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