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SimilarWeb

SimilarWeb is a digital intelligence platform offering a REST API for accessing website traffic estimates, audience demographics, keyword analytics, competitive benchmarking, app intelligence data, and lead generation insights. The API provides real-time and historical data covering traffic sources, search behavior, technographics, e-commerce shopper intelligence, and firmographic company data, enabling developers to integrate market intelligence into applications, dashboards, and data pipelines. The current generation is API V5, launched March 2026, which unified the REST and Batch API keys, added multi-metric requests, and shipped a first-party hosted MCP server at mcp.similarweb.com for AI agents; legacy v1-v4 REST endpoints carry a published sunset date of 2026-10-06.

agent ready

Reference-quality API operations across every facet — a rich contract, published governance, transparent operations, and machine-readable commercial terms.

Kin Score

API Evangelist profiles SimilarWeb the way a machine reads it — 45 machine-readable artifacts across 2 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.

Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — SimilarWeb scores 67.0/100 (exemplar), with a separate agent-readiness read of 50/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.

Kin Score

This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance. Every facet and dimension name is a link: it opens that measurement's page on APIs.io, where the rating runs across the whole catalog — the exact checks that feed it, how every profiled provider distributes on it, and who is at the top of it.

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
Composite quality — 67.0/100 · exemplar
Contract Quality 17.7 / 25
Access Clarity 18.7 / 20
Discoverability 7.6 / 10
SimilarWeb Kin Score — API readiness rating by API Evangelist

Put this on your own site. The badge is drawn live from SimilarWeb's current Kin Score — paste it once and it updates itself every time the score is recomputed. It follows your visitor's light or dark setting, and it links back here so anyone who sees it can read the full breakdown.

<!-- Kin Score · API Evangelist -->
<a href="https://providers.apievangelist.com/providers/similarweb/"
   title="SimilarWeb on API Evangelist — API profile and Kin Score">
  <img src="https://apis.io/badge/similarweb.svg"
       alt="SimilarWeb Kin Score — API readiness rating by API Evangelist" width="150" height="150" loading="lazy">
</a>

More shapes, themes and sizes → · Score as JSON · How badges work

How we profile SimilarWeb

Each block below is one kind of artifact we hold for SimilarWeb. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.

APIs 14

Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.

Individual APIs this provider publishes, each with its own machine-readable definition.

SimilarWeb Batch API

The SimilarWeb Batch API is optimized for large-scale bulk data extraction, supporting jobs of up to one million domains per request. It delivers data asynchronously to cloud st...

SimilarWeb Account API

Account credits, capabilities, and usage information

SimilarWeb App Intelligence API

Mobile app downloads, active users, sessions, and demographics

SimilarWeb Credits API

Batch API credit management

SimilarWeb Geography API

Geographic distribution of website traffic

SimilarWeb Integrations API

Manage cloud storage integrations (S3, GCS, Snowflake)

SimilarWeb Keywords API

Keyword analytics including organic and paid keyword data

SimilarWeb Lead Enrichment API

Lead enrichment combining firmographics and web analytics

SimilarWeb Rankings API

Global, country, and industry rank data

SimilarWeb Reports API

Submit, track, and retrieve bulk data report requests

SimilarWeb Similar Sites API

Similar website discovery

SimilarWeb Traffic and Engagement API

Website traffic visits, bounce rate, pages per visit, visit duration

SimilarWeb Traffic Sources API

Marketing channel traffic breakdown including organic, paid, referral, social, and display

SimilarWeb Webhooks API

Webhook subscription management for data-ready notifications

Scroll within the panel for all 14 ·

Open Collections 14

Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Scroll within the panel for all 14 ·

MCP Servers 1

Model Context Protocol servers expose these APIs directly to AI agents. We profile them because agent-native access is the fastest-growing way this provider's capabilities actually get used.

Model Context Protocol servers that expose these APIs to AI agents.

SimilarWeb MCP Server

Similarweb operates a first-party hosted (remote) MCP server at https://mcp.similarweb.com that exposes its Web, Search and App intelligence datasets as MCP tools. It is not an ...

MCP SERVER

Pricing Plans 1

Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the things the Kin Score reads for access clarity — renamed from commercial clarity in rubric 0.12, because a free statutory interface has access terms and no commercial ones.

Published pricing tiers and plan structures.

Rate Limits 1

Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.

Documented rate limits and quota policies.

Similarweb Rate Limits

3 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.

Cost, billing, and metering signals for API financial operations.

Event Specifications 1

Not every API is request/response. AsyncAPI describes the event-driven and streaming side — the webhooks and channels — so the asynchronous half of the interface is documented the same way the synchronous half is.

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Semantic Vocabularies 1

JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.

JSON-LD contexts and semantic vocabularies used across these APIs.

Similarweb Context

7 classes · 49 properties

JSON-LD

Spectral Rules 1

Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.

SimilarWeb API Rules

6 rules · 5 warnings

SPECTRAL

JSON Schema 2

Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.

Standalone JSON Schema definitions for this provider's data models.

SimilarWeb Geography Response

2 properties

JSON SCHEMA

Examples 3

Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.

Example request and response payloads for these APIs.

Security Posture 3

Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Similarweb Authentication

apiKey/http · 3 schemes

SECURITY

Similarweb Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Similarweb Trust Center

SOC 2 Type II, ISO 27001

SECURITY

Scopes 1

OAuth scopes are the vocabulary of least-privilege access. Profiling them shows exactly what an integration — or an agent acting on a user's behalf — is allowed to do.

OAuth scopes governing access to this provider's APIs.

Similarweb Scopes

1 scope · authorizationCode

1 scopes

SCOPES

Agentic Access 1

An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.

Recommended x-agentic-access execution contracts for AI agents.

Similarweb Agentic Access

27 operations · 8 acting

27 operations · 8 acting

AGENTIC

Resources

Every other property we hold for SimilarWeb — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.

Documentation 2

Reference material describing how the API behaves

Build 3

SDKs, sample code, and the tooling you integrate with

Company 3

The organization behind the API

Other 3

Properties that don't map to a standard resource type

← All providers · Data indexed from github.com/api-evangelist/similarweb · machine-readable index on apis.io

Where this information came from

This is an independent, third-party profile of SimilarWeb, published by API Evangelist. We do not operate, host, resell, or support these APIs, and we are not affiliated with or endorsed by the company unless stated above. Everything here is built from publicly available information — the company's own site, developer portal, documentation, public repositories, and the specifications it publishes for public use. Nothing is obtained by breaching a system, defeating an access control, or using credentials.

The Kin Score and Agent Readiness rating are independently calculated assessments of a company's public API artifacts, scored against a published rubric. They are not certifications, endorsements, security assessments, or audits.

Corrections, re-scores, and removal are free — no partnership or purchase required, and you do not need to justify the request. A removed company is recorded as unrated, never scored zero for having asked. Acknowledgement within one business day; removal within two.

info@apievangelist.com · Read the full data-sourcing policy →
On a security or compliance team? Put security in the subject line and you will get a person, not a form — we will tell you exactly which public URLs this profile was built from.