CoStar Group website screenshot

CoStar Group

CoStar Group is the dominant commercial and residential real estate data, analytics, and marketplace company. The portfolio spans the flagship CoStar commercial real estate intelligence platform, LoopNet (CRE marketplace), Apartments.com network (residential rentals, including ForRent.com and Westside Rentals), Homes.com and Homesnap (for-sale residential), Ten-X (online CRE auctions), BizBuySell (business-for-sale marketplace), STR (hotel data), Visual Lease (lease management), Matterport (3D spatial capture), and international properties including OnTheMarket (UK), Emporis (Germany), and a controlling stake in Domain Group (Australia). Distribution to partners is via enterprise data licensing, syndication feeds, and brand-specific marketplace tooling rather than a public self-serve developer portal.

CoStar Group publishes 14 APIs on the APIs.io network. Tagged areas include Commercial Real Estate, Residential Real Estate, Real Estate Data, Marketplace, and Analytics.

CoStar Group’s developer surface includes product news and 6 more developer resources.

🌐 Visit website 📡 Source on GitHub
17.8/100 emerging ▬ flat Agent 3/100 human only Full breakdown ↓
scored 2026-09-25 · rubric v0.23.0
AccessFree
14 APIs
Commercial Real EstateResidential Real EstateReal Estate DataMarketplaceAnalyticsListingsPropTech

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-25 · rubric v0.23.0
Composite quality — 17.8/100 · emerging
Contract Quality 0.0 / 21
Developer Ergonomics 1.6 / 17
Access Clarity 5.9 / 17
Operational Transparency 2.1 / 11
Contract Governance 0.0 / 10
Discoverability 6.1 / 9
Regulatory Posture 1.6 / 15
Agent readiness — 3/100 · human only
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 10
Documented Reversibility 0 / 6
MCP Server 0 / 12
Machine-Readable Auth 0 / 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
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Delegated User Identity 0 / 6
Protected Resource Metadata 0 / 5
Registration Without a Human 0 / 6
Agentic Commerce Well-Known Document 0 / 5
Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.
Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.
The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/costar: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 14

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

CoStar Commercial Real Estate Platform

CoStar's flagship commercial real estate information platform covering property, tenant, lease, sale, and market analytics across office, industrial, retail, multifamily, and sp...

LoopNet

The largest commercial real estate marketplace in the United States, surfacing CRE listings for sale and lease alongside CoStar-sourced analytics.

Apartments.com Network

Residential rental marketplace network including Apartments.com, ForRent.com, and Westside Rentals, providing listings, leads, and advertising to multifamily owners and managers.

Homes.com

Residential for-sale and rental marketplace operating agent-first branding and search, paired with the Homesnap mobile and agent tooling.

Homesnap

Mobile residential real estate search and agent productivity application that integrates with MLSs and Homes.com.

Ten-X

Online commercial real estate transaction and auction platform for buyers and sellers of CRE assets.

BizBuySell

Online marketplace for buying and selling small and mid-sized businesses, with broker tools and financing partners.

STR (Smith Travel Research)

Hotel benchmarking, performance data, and analytics provider serving the global lodging industry.

Visual Lease

Lease management and lease accounting platform for corporate and real estate tenants.

Matterport

3D spatial data capture platform used to digitise real estate, retail, and built-environment spaces, integrated across CoStar's marketplaces.

OnTheMarket

UK residential property portal acquired by CoStar Group, providing for sale and to let listings with agent tooling.

Emporis

Global building data and imagery provider covering high-rise and commercial structures.

Domain Group

Australian residential real estate marketplace and media company in which CoStar Group acquired a majority stake.

Land.com / Lands of America

Land-for-sale marketplace network covering rural, ranch, recreational, and development land in the United States.

Scroll for all 14

Pricing Plans 1

Published pricing tiers and plan structures.

Costar Plans Pricing

1 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Costar Rate Limits

2 limits

RATE LIMITS

FinOps 1

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

Costar Finops

FINOPS

Security Posture 2

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

Costar Domain Security

TLSv1.3 · DMARC

SECURITY

Costar Trust Center

SOC 2, ISO 27001, PCI DSS, GDPR

SECURITY

Resources

Access & Security 2

Authentication, authorization, and security posture

TrustCenter
TrustCenter
 DomainSecurity
DomainSecurity

Commercial 1

Pricing, plans, and the legal terms of use

CoStar
CoStar

Company 4

The organization behind the API

Website
Website
 Investors
Investors
 News
News
 LinkedIn
LinkedIn

Source (apis.yml)

apis.yml Raw ↑ 
aid: costar
name: CoStar Group
url: https://raw.githubusercontent.com/api-evangelist/costar/refs/heads/main/apis.yml
description: CoStar Group is the dominant commercial and residential real estate data, analytics, and marketplace company.
  The portfolio spans the flagship CoStar commercial real estate intelligence platform, LoopNet (CRE marketplace), Apartments.com
  network (residential rentals, including ForRent.com and Westside Rentals), Homes.com and Homesnap (for-sale residential),
  Ten-X (online CRE auctions), BizBuySell (business-for-sale marketplace), STR (hotel data), Visual Lease (lease management),
  Matterport (3D spatial capture), and international properties including OnTheMarket (UK), Emporis (Germany), and a controlling
  stake in Domain Group (Australia). Distribution to partners is via enterprise data licensing, syndication feeds, and brand-specific
  marketplace tooling rather than a public self-serve developer portal.
kind: company
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - none
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: free
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Free
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/costar.png
tags:
- Commercial Real Estate
- Residential Real Estate
- Real Estate Data
- Marketplace
- Analytics
- Listings
- PropTech
tags_raw:
- Commercial Real Estate
- Residential Real Estate
- Real Estate Data
- Marketplaces
- Analytics
- Listings
- PropTech
created: '2026-05-23'
modified: '2026-05-23'
specificationVersion: '0.23'
apis:
- aid: costar:costar
  name: CoStar Commercial Real Estate Platform
  description: CoStar's flagship commercial real estate information platform covering property, tenant, lease, sale, and market
    analytics across office, industrial, retail, multifamily, and specialty CRE asset classes. Data is licensed to enterprise
    customers and partners under contract.
  humanURL: https://www.costar.com
  baseURL: https://www.costar.com
  tags:
  - Commercial Real Estate
  - Analytics
  - Property Data
  properties:
  - type: Documentation
    url: https://www.costar.com
- aid: costar:loopnet
  name: LoopNet
  description: The largest commercial real estate marketplace in the United States, surfacing CRE listings for sale and lease
    alongside CoStar-sourced analytics.
  humanURL: https://www.loopnet.com
  baseURL: https://www.loopnet.com
  tags:
  - Commercial Real Estate
  - Marketplace
  - Listings
  properties:
  - type: Documentation
    url: https://www.loopnet.com
- aid: costar:apartments-com
  name: Apartments.com Network
  description: Residential rental marketplace network including Apartments.com, ForRent.com, and Westside Rentals, providing
    listings, leads, and advertising to multifamily owners and managers.
  humanURL: https://www.apartments.com
  baseURL: https://www.apartments.com
  tags:
  - Residential Rentals
  - Multifamily
  - Marketplace
  properties:
  - type: Documentation
    url: https://www.apartments.com
- aid: costar:homes-com
  name: Homes.com
  description: Residential for-sale and rental marketplace operating agent-first branding and search, paired with the Homesnap
    mobile and agent tooling.
  humanURL: https://www.homes.com
  baseURL: https://www.homes.com
  tags:
  - Residential Real Estate
  - For Sale
  - Marketplace
  properties:
  - type: Documentation
    url: https://www.homes.com
- aid: costar:homesnap
  name: Homesnap
  description: Mobile residential real estate search and agent productivity application that integrates with MLSs and Homes.com.
  humanURL: https://www.homesnap.com
  baseURL: https://www.homesnap.com
  tags:
  - Residential Real Estate
  - Mobile
  - MLS
  properties:
  - type: Documentation
    url: https://www.homesnap.com
- aid: costar:ten-x
  name: Ten-X
  description: Online commercial real estate transaction and auction platform for buyers and sellers of CRE assets.
  humanURL: https://www.ten-x.com
  baseURL: https://www.ten-x.com
  tags:
  - Commercial Real Estate
  - Auctions
  - Transaction
  tags_raw:
  - Commercial Real Estate
  - Auctions
  - Transactions
  properties:
  - type: Documentation
    url: https://www.ten-x.com
- aid: costar:bizbuysell
  name: BizBuySell
  description: Online marketplace for buying and selling small and mid-sized businesses, with broker tools and financing partners.
  humanURL: https://www.bizbuysell.com
  baseURL: https://www.bizbuysell.com
  tags:
  - Business For Sale
  - Marketplace
  - Small Business
  tags_raw:
  - Business For Sale
  - Marketplace
  - SMB
  properties:
  - type: Documentation
    url: https://www.bizbuysell.com
- aid: costar:str
  name: STR (Smith Travel Research)
  description: Hotel benchmarking, performance data, and analytics provider serving the global lodging industry.
  humanURL: https://str.com
  baseURL: https://str.com
  tags:
  - Hospitality
  - Hotel Data
  - Benchmarking
  properties:
  - type: Documentation
    url: https://str.com
- aid: costar:visual-lease
  name: Visual Lease
  description: Lease management and lease accounting platform for corporate and real estate tenants.
  humanURL: https://visuallease.com
  baseURL: https://visuallease.com
  tags:
  - Lease Management
  - Lease Accounting
  - Corporate Real Estate
  properties:
  - type: Documentation
    url: https://visuallease.com
- aid: costar:matterport
  name: Matterport
  description: 3D spatial data capture platform used to digitise real estate, retail, and built-environment spaces, integrated
    across CoStar's marketplaces.
  humanURL: https://matterport.com
  baseURL: https://matterport.com
  tags:
  - 3D Capture
  - Spatial Data
  - PropTech
  properties:
  - type: Documentation
    url: https://matterport.com
- aid: costar:onthemarket
  name: OnTheMarket
  description: UK residential property portal acquired by CoStar Group, providing for sale and to let listings with agent
    tooling.
  humanURL: https://www.onthemarket.com
  baseURL: https://www.onthemarket.com
  tags:
  - Residential Real Estate
  - United Kingdom
  - Marketplace
  properties:
  - type: Documentation
    url: https://www.onthemarket.com
- aid: costar:emporis
  name: Emporis
  description: Global building data and imagery provider covering high-rise and commercial structures.
  humanURL: https://www.emporis.com
  baseURL: https://www.emporis.com
  tags:
  - Building Data
  - Imagery
  - Real Estate
  tags_raw:
  - Building Data
  - Imagery
  - Real Estate
  - Real-Estate
  properties:
  - type: Documentation
    url: https://www.emporis.com
- aid: costar:domain-group
  name: Domain Group
  description: Australian residential real estate marketplace and media company in which CoStar Group acquired a majority
    stake.
  humanURL: https://www.domain.com.au
  baseURL: https://www.domain.com.au
  tags:
  - Residential Real Estate
  - Australia
  - Marketplace
  properties:
  - type: Documentation
    url: https://www.domain.com.au
- aid: costar:lands-of-america
  name: Land.com / Lands of America
  description: Land-for-sale marketplace network covering rural, ranch, recreational, and development land in the United States.
  humanURL: https://www.land.com
  baseURL: https://www.land.com
  tags:
  - Land
  - Marketplace
  - Rural
  properties:
  - type: Documentation
    url: https://www.land.com
common:
- type: TrustCenter
  url: security/costar-trust-center.yml
- type: DomainSecurity
  url: security/costar-domain-security.yml
- type: Website
  url: https://www.costargroup.com
- type: CoStar
  url: https://www.costar.com
- type: Investors
  url: https://www.costargroup.com/investors
- type: News
  url: https://www.costargroup.com/news
- type: LinkedIn
  url: https://www.linkedin.com/company/costar-group/
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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