REST API · MCP server

Collector-car auction data for your code and your AI agent.

400k+ completed sales plus live auctions from 19 auction houses, normalized into one schema. Query it over REST, or connect Claude, ChatGPT, or Cursor over MCP.

Get free API key View docs

No credit card · first query in about a minute

200 OK

GET /auctions?make=Hummer&model=H1&limit=1

{
  "data": [
    {
      "id": 15954362,
      "source": "bringatrailer",
      "title": "1997 AM General Hummer Four-Door Wagon",
      "auction_status": "sold",
      "price": 43000,
      "auction_end_at": "2026-10-04 18:21:49",
      "auction_end_precision": "exact",
      "year": 1997,
      "listing_make": "Hummer",
      "listing_model": "H1"
    }
  ]
}

Trusted by

BidBetter

400k+
Completed sales, normalized: 19
Auction sources, one schema: 15 min
Refresh on completed sales

Sources

Bring a Trailer
Cars & Bids
Hemmings
AutoHunter
Hagerty
PCAR Market
All Collector Cars
Gooding & Co
RM Sotheby's
Barrett-Jackson
Sotheby's Motorsport
Car & Classic
The Market
Broad Arrow
MB Market
Mecum Auctions
PistonHeads
Collecting Cars
Bonhams

Use cases

What teams build on it.

Pricing tools, bidding copilots, valuation agents, and alerting, all off the same feed. BidBetter is one of the teams already shipping on it.

BuildWhat it doesEndpointsStatus

Access

Three ways in. One key.

Start free, no card. Lookups against /makes and /models never count toward your quota.

REST

Query it from anything

Completed sales, live listings, bid trails, and price stats over plain HTTPS with a bearer key.

curl "https://api.oldcarsdata.com/auctions\
?make=Porsche&model=911&limit=10" \
  -H "Authorization: Bearer $OCD_API_KEY"

Endpoint reference

MCP

Hand it to your agent

Tools like search_auctions, get_price_stats, and list_live_auctions for Claude, ChatGPT, Cursor, or your own agent.

claude mcp add --transport http --scope user \
  oldcarsdata https://api.oldcarsdata.com/mcp

MCP setup

SPEC

Generate a typed client

A full OpenAPI schema, so your client, types, and response validation come for free.

npx openapi-typescript \
  https://api.oldcarsdata.com/openapi.json \
  -o oldcarsdata.d.ts

OpenAPI schema

No code required

Dealers and appraisers: just ask.

Connect Claude or ChatGPT to Old Cars Data once. Then ask about any car in plain English and get answers grounded in real auction results.

Price inventory

Check trade-ins and stock against what actually sold, not asking prices.

Back up appraisals

Cite comparable sales with a link to each original listing.

Watch the block

See what is crossing the block right now before you bid.

Connect Claude or ChatGPT

API access

Simple API pricing.

Start free, get a key immediately, and scale when the data is powering production work. Calls to makes and models are unmetered.

Starter

Free

10 metered requests every month

REST API key
MCP server access
Live auction beta access

Get free key

1k

$49/mo

1,000 metered requests per month

Full history + live beta
All auction platforms
API + MCP commercial use

Start with 1k

10k

$199/mo

10,000 metered requests per month

Full history + live beta
All auction platforms
Higher-volume integrations

Start with 10k

100k

$699/mo

100,000 metered requests per month

Full history + live beta
All auction platforms
Large-scale data products and agents

Start with 100k

All plans are month-to-month. No long-term contract.

Reference notes

Frequently asked questions.

Those are consumer valuation guides for mainstream used cars. Old Cars Data is a developer-first API of actual collector-car auction outcomes — completed sales, live listings, and bid trails normalized across nineteen specialist sources.

Your first query is a minute away.

Free key, no card. Comps, live listings, and bid trails from the same feed, over REST or MCP.

Get free API key View docs