Large marketplace for new and used cars, with extensive pricing and dealer comparisons.
Online-first used-car retailer; lets you purchase, finance, trade in, and arrange delivery online.
One of the largest vehicle marketplaces, with listings from dealers and private sellers.
Major new and used vehicle marketplace with dealer listings, reviews, pricing tools, and research.
Large used-car retailer with online shopping, financing, trade-ins, and vehicle delivery/pickup options.
Excellent for researching vehicle values, prices, reviews, and finding cars for sale.
Strong vehicle research, pricing, reviews, dealer listings, and car-shopping tools.
New and used vehicle marketplace emphasizing pricing transparency and dealer offers.
Search engine/marketplace aggregating new and used vehicle listings.
Particularly useful for used cars because you can research vehicle-history reports alongside listings. Carfax is currently one of the most visited automotive websites in the U.S.
Online auctions specializing in enthusiast-oriented modern and collectible vehicles.
Very popular online auction marketplace for enthusiast, classic, collectible, and interesting vehicles.
Online marketplace for cars, trucks, motorcycles, parts, and other vehicles.
Huge local marketplace where private sellers and dealers advertise vehicles.
Long-running classified marketplace with substantial private-party used-car listings.
Used-car retailer offering online shopping, financing, trade-ins, and delivery in many areas. It is also among the sites highlighted in current 2026 online-car-buying comparisons.
An online automotive retailer historically known for online used-car sales. Note: its consumer vehicle-sales operations have changed significantly, so I would verify current availability before relying on it.
Particularly useful for classic, collector, and specialty vehicles.
AutoTrader deserves special mention because of its enormous dealer inventory and search tools; it remains one of the most visited automotive marketplaces globally.
Toyota / Ford / Tesla and other manufacturer websites
For a new vehicle, don't overlook the manufacturer's own site. You can configure vehicles, see inventory, locate dealers, and in some cases complete much of the purchasing process online. YouGov's research has also found manufacturer websites among the most-used resources for Americans researching a car purchase.
Our recommendation
If I were shopping for a car today, I'd start with these five:
CarGurus — best overall for comparing listings and prices
Carvana — best for a highly online buying experience
Cars.com — excellent all-around marketplace
CarMax — particularly convenient for used cars
Then I'd use KBB + Edmunds + Carfax to determine whether the asking price is reasonable and investigate the vehicle before buying.