Schema-first
Required fields, composition, enums, examples, and nested models.
Runs in your browser No sign-up OpenAPI 3.2 ready
OpenAPI Schema Viewer
Open OpenAPI or Swagger JSON and YAML, search endpoints and models,
follow $ref relationships, and spot structural issues —
privately in this browser tab.
Local by default. Pasted text and files never go to our server.
OpenAPI schema viewer workspace
Drop the OpenAPI file
JSON, YAML, or YML · up to 5 MB
The built-in sample is loaded so you can inspect the product before
choosing a file. Descriptions render as inert text; external
$ref targets are never fetched automatically.
Reference-aware
Jump through internal refs, see backlinks, broken targets, and cycles.
Built for large specs
Filter endpoints, operation IDs, tags, models, and property names.
Read-only by design
Copy cURL skeletons without sending API requests or storing credentials.
Three steps, no setup
How to view an OpenAPI schema
Use a local file for confidential contracts, paste a snippet while debugging, or fetch a public document directly from its host.
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01
Open the source
Choose JSON or YAML, drag a file onto the workspace, paste text, enter a CORS-enabled HTTPS URL, or keep the sample.
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02
Find the surface
Search paths, methods, summaries, tags, operation IDs, models, property names, formats, and descriptions.
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03
Follow the contract
Open requests and responses, jump through reusable schemas, copy pointers and examples, then review diagnostics.
One document, two questions
See API behavior and data shape together
Documentation renderers emphasize endpoints. Generic JSON viewers emphasize raw structure. This viewer keeps paths and schemas linked so you can move from an operation to its model and back.
Endpoint explorer
Inspect path and webhook operations, parameters, request bodies, responses, media types, security requirements, servers, deprecation, and operation IDs.
Schema explorer
Read objects, arrays, required properties, nullable unions,
formats, constraints, examples, enums, additional properties, and
allOf, oneOf, or anyOf.
Reference map
Visualize reusable-model dependencies, open internal references, find who points back to a model, and identify unresolved or cyclic links without dereferencing forever.
Actionable output
Copy a JSON Pointer, schema JSON, generated example, endpoint path, or ready-to-edit cURL skeleton. Download normalized JSON when another tool needs it.
Version-honest viewing
Swagger 2.0 through OpenAPI 3.2
Version detection changes where the viewer looks for reusable models, request bodies, servers, and security definitions. New or unknown 3.x fields remain visible instead of causing blanket rejection.
DocumentModelsViewer behavior
OpenAPI 3.2 / 3.1
components.schemas
Reads JSON Schema-aligned types, webhooks, composition, and modern request bodies.
OpenAPI 3.0
components.schemas
Reads paths, servers, content media types, callbacks, security, and reusable components.
Swagger 2.0
definitions
Reads host/basePath, body parameters, response schemas, and security definitions.
Specification reference: OpenAPI Specification 3.2.0. Reading shared structures is not the same as proving every version-specific rule.
Know where the bytes go
Private inputs with explicit network boundaries
“Secure” is vague. The input mode determines the network behavior, so the viewer states it before you commit a document.
Paste, file, and drop
The source is read with browser APIs and kept in this tab's memory. It is not posted to this site.
Load from URL
Your browser contacts the source host directly without our proxy, credentials, or referrer. The host must allow CORS.
Share locally
Small documents can be compressed into the URL fragment. The server does not receive fragments, but anyone with the full link can read the source.
External references
External $ref targets are listed as diagnostics and
are never fetched behind your back.
Choose the right tool
OpenAPI viewer vs editor vs validator
You need to understand a contract
- Quickly browse unfamiliar endpoints and schemas.
- Review a confidential draft without server upload.
- Trace internal references and copy useful artifacts.
- Find likely structural problems before deeper validation.
You need to author the contract
Choose a dedicated editor for autocomplete, code actions, refactoring, bundling, and continuous design feedback.
You need conformance gates
Choose a version-specific validator or linter in CI for complete rules, organization policies, and reproducible build failures.
Practical answers
OpenAPI schema viewer FAQ
Is my OpenAPI schema uploaded?
No. Pasted text and local files are parsed in the current browser tab. Loading a URL makes a direct request from your browser to that source host; it does not pass through our server.
Which OpenAPI versions can I view?
The viewer reads Swagger 2.0 and OpenAPI 3.x documents, including OpenAPI 3.2, in JSON or YAML. It renders stable shared structures and keeps unknown fields visible, but does not promise full conformance validation.
Does the viewer fetch external $ref files?
No. Internal references such as
#/components/schemas/Book can be followed inside the
document. External file or URL references are reported and never
fetched automatically.
Why did loading a schema URL fail?
Browsers require the source host to allow cross-origin requests with CORS, and an HTTPS page cannot fetch an insecure HTTP document. Download the file and open it locally when the host does not allow browser access.
Can I share a schema without uploading it?
For documents up to 200 KB, “Share locally” can compress the source into the URL fragment. Fragments are not sent in HTTP requests. Still treat the full URL as confidential because recipients, chat systems, browser history, and screenshots can expose it.
Is this a full OpenAPI validator?
No. The diagnostics cover syntax, missing core fields, broken internal refs, cycles, duplicate operation IDs, and path parameter mismatches. Use a dedicated version-specific validator or linter in CI for complete conformance.
Can it send live API requests?
The viewer intentionally stays read-only. It generates a cURL skeleton that you can review and edit, but it does not collect credentials or send requests that might change real data.
What is the file size limit?
Local, pasted, and URL-loaded documents are limited to 5 MB to keep the browser responsive. Share links use a smaller 200 KB pre-compression limit because extremely long URLs are unreliable.