REST API
Also known as: RESTful API, HTTP API
Quick definition
A REST API is an HTTP-based programmatic interface following the REST architectural style — using standard HTTP verbs (GET, POST, PUT, DELETE) on resource-based URLs. Most modern web APIs are REST or REST-flavored; REST is the standard for social media APIs, payment APIs, scheduling APIs, and most SaaS integrations.
What is a REST API?
REST (Representational State Transfer) is an architectural style for building web APIs, formalized by Roy Fielding in his 2000 PhD dissertation. A REST API exposes resources (posts, users, orders) at URL paths and uses standard HTTP verbs to operate on them: GET to retrieve, POST to create, PUT to update, DELETE to remove. Responses are typically JSON. The state of resources lives on the server; clients send requests to query or modify that state.
In practice, 'REST API' is the colloquial term for any HTTP+JSON API loosely following these conventions, even when they don't strictly adhere to all of Fielding's REST principles. Most public APIs you'll encounter — Stripe, Twilio, GitHub, Slack, the social media schedulers, and CodivUpload's own — are 'REST-flavored'. Strict REST purism is rare; practical REST is the standard.
REST conventions in practice
Five conventions you'll see across nearly every REST API. (1) Resource-based URLs — `/v1/posts`, `/v1/profiles/{id}`. (2) HTTP verbs map to operations — POST creates, GET reads, PUT updates fully, PATCH updates partially, DELETE removes. (3) JSON request and response bodies — Content-Type: application/json. (4) HTTP status codes — 200 success, 201 created, 400 bad request, 401 unauthorized, 404 not found, 500 server error. (5) Authorization header — Bearer tokens are standard.
Most APIs also expose pagination (cursor-based or page-number-based), filtering via query parameters, error response shapes (`{error: {code, message}}`), and rate limiting via `X-RateLimit-*` headers. These aren't REST per se but de-facto standards in modern API design.
REST vs GraphQL vs gRPC
Three competing approaches. REST = HTTP + JSON, resource-oriented, widely supported. GraphQL = single endpoint, query language, client specifies what fields to return; better for complex data fetching but heavier infrastructure. gRPC = HTTP/2 + Protocol Buffers, type-safe, fast, but harder to debug; popular for internal microservices, less common in public APIs. For social media APIs and most SaaS integrations, REST remains the default because of its broad tool ecosystem and conceptual simplicity.
CodivUpload's API is REST-flavored — POST /v1/posts to publish, GET /v1/posts/{id} to retrieve status, etc. The OpenAPI specification at api.codivupload.com/public-openapi.json documents every endpoint formally.
Frequently asked questions
Is REST the only API style?+
No, but the most common for public web APIs. GraphQL has grown for complex data needs; gRPC dominates internal microservices. For 90%+ of public-facing SaaS APIs, REST is the standard choice.
What's the difference between REST and HTTP?+
HTTP is the underlying protocol (the verbs and structure). REST is an architectural style for using HTTP for APIs. All REST APIs use HTTP; not all HTTP APIs are RESTful (some are RPC-style, some are GraphQL, etc.).
Do I need to be a REST expert to use a REST API?+
No. Most REST APIs are simple enough to use without deep theoretical knowledge — read the docs, send the requests, parse the responses. The architectural details matter for API designers; consumers mostly need to know how to authenticate, what endpoints exist, and what response shapes to expect.
REST API for 11 social platforms — one endpoint
CodivUpload's REST API lets you publish, schedule, retrieve analytics, manage profiles across all 11 platforms from a single base URL. OpenAPI spec auto-generates SDKs.
See API docsRelated glossary terms