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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.

agent ready

Real signal across most facets with visible, nameable gaps — the contract exists but is thin, or the portal is good while governance and commercial terms are absent.

Kin Score

API Evangelist profiles SimilarWeb the way a machine reads it — 27 machine-readable artifacts across 14 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 55.7/100 (developing), with a separate agent-readiness read of 48/100 (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.

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 55.7/100 · developing
Contract Quality 17.8 / 25
Developer Ergonomics 4.3 / 20
Commercial Clarity 10.0 / 20
Operational Transparency 4.8 / 13
Governance 8.8 / 12
Discoverability 10.0 / 10
Agent readiness — 48/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 15 / 15
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3

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 ·

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 six things the Kin Score reads for commercial clarity.

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.

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 2

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 · 2 schemes

SECURITY

Similarweb Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

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 1

Reference material describing how the API behaves

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

Build 1

SDKs, sample code, and the tooling you integrate with

Access & Security 2

Authentication, authorization, and security posture

Operate 1

Status, limits, changes, and where to get help

Commercial 3

Pricing, plans, and the legal terms of use

Company 3

The organization behind the API

Other 1

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