CLASSIC.COM API Offering— Partner Guide

Overview

The CLASSIC.COM API gives authorized partners programmatic access to the data that powers CLASSIC.COM: one of the most comprehensive specialty car databases in the world. Rather than manually browsing the site, your platform or internal tools can pull vehicle data, search sales history, find comparable cars, and generate embeddable market charts automatically.

API access is organized into four Licensed Data Bundles, each corresponding to a progressively deeper level of data access. 

Table of Contents

1. Bundle 1: Market Widget Creation via Taxonomy (Access Level 1) 

2. Bundle 2: Vehicle Taxonomy (Access Level 2) 

3. Bundle 3: Sales History (Access Level 3) 

4. Bundle 4: Comps (Comparable Vehicles) (Access Level 4)

5. Best Practices

6. Getting Access

7. Documentation

Bundle 1: Market Widget Creation via Taxonomy

What It Does

This bundle gives you the ability to programmatically generate embeddable market chart widgets for any vehicle in the CLASSIC.COM database. These are the same charts you see on CLASSIC.COM market pages — live, data-driven sales history charts that you can embed directly on your own website or platform.

A widget displays 5 years of sales history for a specific vehicle market, including sold prices, asking prices, high bids, and a moving average trendline. The chart also shows summary statistics at a glance: number of cars currently for sale, average sale price, total sales count, dollar volume, lowest sale, top sale, and most recent sale.

How It Works

You call the API with a vehicle description, and CLASSIC.COM returns a ready-to-use embed code (an <iframe>) that you drop into your page. The chart is hosted on CLASSIC.COM and loads automatically.

You can specify the vehicle in two ways:

Using names — Provide the make, model, and any available details: year, generation, variant, trim. For example, to generate a widget for a 1986 Porsche 911 Carrera G-Body, you would pass: Year: 1986, Make: Porsche, Model: 911, Generation: G-Body, Variant: Carrera.

Using taxonomy IDs — Once you've explored the vehicle taxonomy (Bundle 2), you can use CLASSIC.COM's internal IDs instead of names for more precise results.

Using a VIN — When a VIN is available and exists in the CLASSIC.COM database, passing it is the recommended approach. The API will use the VIN to identify the specific vehicle and generate the most accurate market match possible.

What the Embed Looks Like

The embed code is a single line that renders a full chart in your page:

<iframe src='https://www.classic.com/widget/[hash]/' width='100%' height='480' style='border:0;'></iframe>

The charts generated look like: 

What You Receive

Along with the embed code, the API returns some about the market that was matched to your input — including the widget's unique ID, the domain it's registered to, the vehicle year, and whether a VIN was used. This lets you verify the widget was generated for the right car before publishing it.

If the Widget Doesn't Match the Right Vehicle

If the chart appears to be showing the wrong market, the most likely cause is that the input wasn't specific enough. Add more detail — generation, variant, trim, and year. When in doubt, passing a VIN eliminates ambiguity entirely, provided the vehicle is in the CLASSIC.COM database. 

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Bundle 2: Vehicle Taxonomy

What It Does

This bundle gives you access to CLASSIC.COM's proprietary vehicle classification system — a structured, hierarchical library of every make, model, generation, variant, trim, and engine in the collector car world.

The taxonomy is the foundation that makes precise vehicle identification possible. It solves a persistent problem in the collector car space: there are many ways to refer to the same car, and many cars that share names but are meaningfully different. The taxonomy maps all of it to a single, unambiguous structure.

The Taxonomy Hierarchy

Every vehicle is classified using 5 hierarchichal levels + powertrain (engine details). From the broadest level down to the most specific:

Make → Model → Generation → Variant → Trim + Engine

Two examples using Porsche and Ford taxonomies: 

What Each Level Means

Make — The manufacturer (Porsche, Ferrari, BMW, Ford, etc.).

Model — The nameplate under that manufacturer, with an overall production year span (e.g., the Porsche 911 runs from 1965 to present).

Generation (Model Generation) — A distinct production era within the model's life, typically representing a significant mechanical or design update. For the 911, this includes generations like the G Body, 964, 993, 996, 997, 991, and 992 families — each with its own year range and set of available variants and engines.

Variant (Model Variant) — A specific series within a model, such as GT3, Turbo, Targa, or Carrera. A variant can span multiple generations, and each carries its own year ranges and list of available trims and engines.

Trim — The most granular factory differentiation: a specific configuration or special edition within a variant (e.g. Touring, Clubsport, 40th Anniversary).

Engine (Powertrain) — The engine configuration, described by displacement, layout, and any factory designation (e.g., 4.0L Flat-6, 3.3L Turbo Flat-6, 3.6L H6 X-51).

Why This Matters for Partners

Precision matters in classic car valuation. A 991.2 GT3 Touring is a meaningfully different car from a 991.2 GT3 Standard — different rarity, different demand, different price. The taxonomy lets you query at exactly the right level of specificity across all subsequent API calls.

For production integrations, we recommend using taxonomy IDs (stable internal identifiers) rather than plain text names, which can be ambiguous. You look up the IDs once using the taxonomy, then reference them in all your downstream queries.

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Bundle 3: Sales History

What It Does

This bundle provides access to CLASSIC.COM's sales history database — up to 5 years of vehicle listings and auction results, queryable using taxonomy classification and vehicle attributes. It covers listings from auction houses, dealers, and online platforms tracked by CLASSIC.COM.

How You Can Search

By keyword or VIN — Enter a free-text search term or a specific Vehicle Identification Number (or chassis/serial number). Best for exploratory searches or when you have a specific car in mind.

By taxonomy name — Search using make and model names, with optional generation, variant, trim, engine, body style, transmission, and doors. Requires at minimum a make and model name. Good for quick integration before taxonomy IDs are resolved.

By taxonomy ID — The most precise method. Uses CLASSIC.COM's internal taxonomy IDs for unambiguous results. Recommended for production use once IDs are resolved.

By price range — Retrieve all vehicles sold or listed within a specified USD price range, with optional date filters. Useful for market segment analysis or surfacing inventory across a price band.

All search methods support filtering by listing source (all listings, live auction events only, or online-only listings), by sale type (all, auction, or fixed-price), and by date range.

What Data Is Included

Sales History results include two categories of data:

Vehicle Attributes

• Body style (Coupe, Hatchback, Wagon, Pickup, SUV, etc.)
• Number of doors
• Handedness / driver side (LHD, RHD, Center)
• Transmission type (Automatic, Manual)
• Originality / Conservation Status (Original & Highly Original / Restomod & Custom / Project / Modified)
• Exterior color and interior color (broad categories: Red, Black, Silver, Gray, Beige, White, Brown, etc.)
• Drive type
• Title status (Lemon Law, Salvage, State VIN, etc.)
• Engine swap flag (Yes/No)
• Mileage (with unit and TMU flag for total mileage unknown)
• VIN

Listing-Related Fields

• Location: city, state, country, continent, and coordinates
• Listing type: Dealer, Auction, or Extended
• Price: bid prices and asking prices, in original currency and USD
• Lot date: auction close date or last updated date
• Status: For Sale, Sold, Not Sold (High Bid), Withdrawn, etc.
• Primary listing image

You can find out more in the API documentation for the specifics of what is returned in the vehicle objects.

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Bundle 4: Comps (Comparable Vehicles)

What It Does

This bundle provides access to CLASSIC.COM's comparable vehicle engine — a proprietary algorithm that returns a ranked list of up to 30 vehicles that are most similar to a specific car, based on 18+ variables. Results are sorted by relevance score, giving you a clear sense of which comps are the closest match and which are more peripheral.

This is the same feature that appears on every Vehicle Detail Page on CLASSIC.COM. You can see a live example here: classic.com/veh/1985-porsche-911-2dr-coupe-carrera → Comps tab.

What the Algorithm Considers

The relevance ranking accounts for a combination of taxonomy classification (make, model, generation, variant, trim, engine) and vehicle attributes (year, mileage, condition/originality, transmission, color, body style, driver side, location, and more). The more attributes you provide, the more precise the output.

How You Can Search

By VIN — Pass a VIN and CLASSIC.COM will identify the vehicle directly and return comps based on that specific car's profile. This is the most accurate input method.

By taxonomy and attributes — Pass any combination of make, model, generation, variant, trim, engine, year, mileage, condition, transmission, color, body style, driver side, doors, vehicle type, and date range. All fields are optional, but more inputs produce better-matched results.

You can also apply a location filter to prioritize geographically relevant comps.

What You Get Back

The response includes a total count of comparable vehicles found in the database, plus a list of up to 30 individual vehicle records sorted by relevance. Each record in the list includes the full listing detail available in Bundle 3 — price, status, mileage, attributes, location, and the relevance score for that specific comp.

The relevance score (expressed as a percentage) tells you how closely each vehicle matches your input. In practice, scores above 90% represent very close comps; scores in the 80–90% range are still meaningful but represent looser matches on one or more attributes.

Practical Applications

Comps are most valuable in three scenarios: appraising a vehicle before listing or selling, supporting a lending decision with documented market evidence, and building valuation tools that need verifiable comparable transactions rather than algorithmic estimates alone.

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Best Practices

Bundle 1 — Widgets: Always include a VIN when available. It produces the most accurate market match. When using names instead of IDs, be as specific as possible — include generation, variant, trim, and year to avoid the widget matching a broader or incorrect market.

Bundle 2 — Taxonomy: Traverse the hierarchy top-down (Make → Model → Generation → Variant) to resolve IDs before making downstream queries. Do this once as a setup step and store the IDs for reuse. IDs are stable and will not be affected by naming variations or formatting differences.

Bundle 3 — Sales History: Use taxonomy ID-based searches in production for the most precise results. Apply date range filters to scope results to a relevant time window — a 2–3 year lookback tends to reflect current market conditions for most collector car segments. Use name-based searches for prototyping and integration testing before IDs are resolved.

Bundle 4 — Comps: More inputs produce better-ranked results. At minimum include make, model, year, and mileage. For high-value or rare vehicles, add generation, variant, trim, transmission, and originality status. Use the relevance score to determine which comps carry the most weight in a valuation.

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Getting Access

The CLASSIC.COM API is available to authorized third-party partners. Access is granted on a per-integration basis, with bundles licensed according to your use case. To inquire about API access or discuss integration options, contact the CLASSIC.COM at datasupport@classic.com.

Documentation

The CLASSIC.COM API documentation is available at this link.