Car Rental API & Car Hire API: Compare Vehicles and Prices for a Pickup

A car rental API — also called a car hire API in British and Australian English — is a vehicle comparison endpoint. You send a pickup location, dates, and driver age. You get offers you can rank. You do not get a voucher.

This page is the Ktemia contract for that job: POST /v1/cars, the same search in the UI, and a copilot that asks when a field is missing. The route is not live yet. The examples below are the payload we will accept, not a production response with invented rates. Whether you searched “car rental api” or “car hire api,” you landed on the same endpoint.

Key Takeaways

• A car rental API and a car hire API are the same search endpoint. One is American English, the other is British. The contract is identical.
• Booking.com Demand API v3.2: search, then availability, then orders/create — three steps, not one.
• Skyscanner calls theirs Car Hire Live Prices: /create then /poll with a session token. Requires Partnerships approval.
• Car dealer car rentals — dealership rental desks run by Enterprise, Hertz, or local fleet partners — feed the same aggregator inventory.
• Ktemia: one POST, pickup and dates required. 50 free requests a month. Not live.

What is a car rental API?

A car rental API — or car hire API, the same thing in different English — returns vehicles and prices for a pickup location and dates. Booking.com’s Car Rentals overview (retrieved 25 September 2026) describes their Demand API as endpoints to search for, display, and — in Beta — book car rentals using Booking.com inventory. Search is one step. Booking is another. Skyscanner uses the term “car hire” throughout their docs; Booking.com and Expedia use “car rental.” The API contract is the same either way.

Expedia Group’s Rapid Car API claims access to 47,000 vendors across more than 190 countries, with endpoints from search to booking to cancellation. That is a full-stack partner path, not a hobby key.

Most teams typing car rental api want the search step: vehicles, prices, insurance included or not, mileage limits, and a pickup desk. They do not want orders/create. They do not want reconciliation. Mixing them in one integration is how you become a car rental agency by accident.

Search

Pickup, dates, driver age in. Vehicles and prices out. No voucher.

Book

Offer in. Reservation, payment, and a voucher out. Demand API or Rapid.

Redirect

Deep link out. The traveler books on the supplier's site. You earn a commission.

Ktemia is search and compare: cars with flights, hotels, and real estate, in the dashboard or through APIs. A search is not a reservation. That is in the terms. For what the search actually surfaces — vehicle types, provider pricing gaps, and pickup location differences — see the car rental comparison guide.

The real split in the car rental API market is not Hertz vs Sixt. It is aggregator APIs (Booking.com Demand, Skyscanner Car Hire, Expedia Rapid, CarTrawler) versus fleet APIs (Sixt, Hertz, Enterprise direct). Most developers want an aggregator that searches across multiple suppliers. Most “car rental API” and “car hire API” search results send you to a single supplier’s partner portal. A third category — car dealer car rentals — barely appears in API results at all, even though thousands of dealerships rent vehicles through fleet partners. For how Ktemia aggregates across all three — and why the integration tax is the real cost — see the car rental aggregator API post.

What does a car rental search API need?

Three fields are required on Ktemia: pickup location, pickup date/time, and dropoff date/time. Driver age is required by most suppliers for pricing. That is the contract, not a live capture.

Booking.com’s search endpoint (Demand API v3.2) requires route.pickup.location, route.pickup.datetime, route.dropoff.datetime, driver.age, and booker.country. Optional filters include transmission_type, mileage_type, air_conditioning, fuel_types, and depot_location_type (in-terminal, shuttle, downtown).

Skyscanner’s Car Hire Live Prices uses /create with pickup and dropoff locations and dates, market, locale, currency, and driver age. You then /poll with the session token. Their docs note the cheapest quotes often come from slower supply partners — which is why they split the workflow into create-and-poll.

Ktemia’s contract is one POST. When the route is live, the full shape goes into docs. Until then:

import requests

requests.post(
  "https://api.ktemia.com/v1/cars",
  json={
    "pickup": "LHR",
    "dropoff": "LHR",
    "pickup_date": "2026-10-12T10:00:00",
    "dropoff_date": "2026-10-19T10:00:00",
    "driver_age": 30,
  },
)

If pickup location or dates are missing, the call must fail and name what is absent. The copilot must ask. It must not invent Heathrow because the user said “when I land.” That rule matches the flight search API contract — no guessing origin, no guessing pickup.

How is Booking.com’s Demand API for cars structured?

Booking.com’s car rental docs (retrieved 25 September 2026) describe two flows:

Search, look, and redirect (stable). You call /cars/search with the route. You display results. The traveler clicks a URL from the response and books on cars.booking.com. You earn an affiliate commission. You never touched orders/create.

Search, look, and book (Beta). You search, then call /cars/availability for a full price breakdown and optional extras (child seat, GPS). You show terms and conditions. Then you call /orders/create to complete the booking in your app. This flow requires partner approval and is currently in a pilot programme.

The migration guide from their legacy XML API to Demand API is explicit: new credentials, JSON instead of XML, and a modular architecture where depot IDs now specify the exact pickup location (e.g., “Avis at Manchester Airport”) rather than just the airport.

Demand API Endpoint	What it does	What it is not
/cars/search	Vehicles, prices, basic details	Not a booked car
/cars/availability (Beta)	Full breakdown, extras, live pricing	Not a reservation
/cars/terms-and-conditions (Beta)	Legal info before booking	Not a receipt
/orders/create (Beta)	Complete the booking in your app	Not search

Here is the pattern developers miss: Booking.com’s car search is not a full mirror of their consumer site. Their docs say explicitly that not all cars visible on booking.com are available via the Demand API. The API delivers “an integrator-friendly subset of inventory optimised for connected trip solutions.” If your comparison page shows different results than booking.com’s consumer site, that is by design, not a bug.

How does Skyscanner’s Car Hire API work?

Skyscanner’s Car Hire Live Prices API (v1.0, retrieved 25 September 2026) is a create-and-poll model, like their flights API. Skyscanner is the largest API that uses the term car hire rather than car rental — if you searched “car hire api,” their docs are likely what you expected to find.

/create initiates the search. Returns basic results plus a session token and information about agents (supply partners) and vendors (actual car companies).

/poll retrieves the complete result set. You call it repeatedly with the session token until status returns completed. Results include quotes with a deepLink field that takes the traveler to the booking page on the agent’s site.

Key vocabulary from their docs: vendors are the companies that own the cars (Hertz, Sixt, Enterprise). Agents are supply partners where quotes come from. A vendor can also be an agent. Sorting is by cheapest.

This is a redirect model. Skyscanner searches. The traveler books on the supplier’s or agent’s site. No voucher comes through the Skyscanner API. You need a Partnerships application to get an API key.

How does Expedia Rapid Car API compare?

Expedia Group’s Rapid Car API is a full search-to-book path:

1. GET /cars/availability — search with pickup, dropoff, and search radius. Up to 200 cars per request.
2. GET /cars/{car_rental_id}/details — price breakdown, optional extras, and policies.
3. POST /itineraries/car — complete the booking.

Rapid claims access to 47,000 vendors globally. That is a partner-gated API, not a public endpoint. You need to become an Expedia Group partner.

The pattern is the same as with Booking.com and Skyscanner: search is one job, booking is another. If you only need vehicles and prices for a pickup, stop at step 1. If you never process payment, you are a comparison site, not an OTA.

What about CarTrawler and Discover Cars?

CarTrawler is a white-label car rental platform used by airlines and travel companies. Their SDK exposes requestVehicles with availability data, a vehicle limit, and sorting by BEST_PRICE or RECOMMENDED. This is an SDK integration, not a public REST API. You become a CarTrawler partner.

Discover Cars advertises an XML API integration for online travel agencies. Their affiliate program pays 70% of profit on completed rentals. Technical documentation requires partnership approval. This is an affiliate model with API access, not a self-serve search endpoint.

Neither is wrong. Both are gated. If you want a car rental search you control — same contract in the dashboard, the API, and the copilot — that is the Ktemia job.

What about car dealer car rentals?

Car dealer car rentals are vehicles rented from a car dealership rather than a traditional rental counter. Most dealerships do not run their own rental fleet. Instead, they partner with Enterprise, Hertz, or a regional fleet company that operates a rental desk inside the dealership. When a customer’s car is in the shop, the dealer offers a loaner or a short-term rental through that partner.

This matters for APIs because dealer rental inventory feeds into the same aggregator supply chain. When Enterprise places vehicles at a Ford dealership, those cars are searchable through Booking.com Demand, Skyscanner Car Hire, or Expedia Rapid — listed under the Enterprise brand with the dealership’s address as the depot. The vehicle is at a dealer. The API does not know or care. It returns a price and a pickup location.

Some dealerships run genuinely independent rental operations — small fleets of 20–50 cars, often in suburban or rural locations where airport rental counters are sparse. These fleets are harder to find through aggregator APIs because they lack the supply-partner integrations that feed Booking.com or Skyscanner. They are, however, exactly the kind of supply gap a comparison search is designed to surface: if a local dealer’s fleet feeds any aggregator that Ktemia searches, it appears alongside Enterprise and Hertz in the same result set.

The “car dealer car rentals” search intent is split. Half the searchers want a loaner car while their vehicle is being serviced. The other half want to rent from a dealership because they assume newer inventory or lower prices than airport counters. Neither group is looking for an API — they want a vehicle. But if you are building a comparison product that covers non-airport pickups, dealer locations are an inventory class most aggregator UIs bury under “other locations” or “downtown” depot filters.

What must you not guess?

Pickup location and dates. On Booking.com Demand, that is route.pickup.location and route.pickup.datetime. On Skyscanner, that is the pickup location and date in /create. On Ktemia, that is pickup, pickup_date, dropoff_date.

If the user says “I need a car when I get there,” ask. When do you arrive? Which airport? How long? Do not fill LHR because a blog example used it. On Free, you get 50 API requests a month. A wrong pickup is a spent call on a car at the wrong desk.

Agents should load “search cars, ask if unclear,” not “pick the nearest airport and hope.” That rule matches flights MCP and the AI travel deal finder contract. Same platform. Same discipline.

What does a free car rental API include?

As of 23 October 2026, the pricing page publishes four plans. Free is $0: dashboard, 50 API requests a month, and search in the UI for flights, stays, cars, and homes. Pro is $29.99 a month with 20,000 API requests at 20 per second. Business is $299 with 250,000 requests at 250 per second, plus MCP servers. Enterprise is a call.

Those caps are one shared monthly pool. Car searches, flight searches, and hotel searches all draw from the same number. A wrong pickup burns a call you cannot spend on flights later.

Start with vehicles you can compare.

A car rental API — or car hire API, same endpoint — compares. It does not issue a voucher, and it does not process the payment. Whether the vehicle sits at an airport counter, a downtown depot, or a car dealer’s lot, the search contract is the same: pickup, dates, prices. The Ktemia contract is one POST, pickup and dates required, and a copilot that asks instead of guessing. The endpoint is not live. When it is, this page will show a dated response, not invented Hertz rates.

Start from product and the pricing caps. If you are building the comparison, not the checkout, you are on the right URL.