Bid Inside is an online auction network and marketplace that connects collectors with specialist auction houses and online stores. Its platform brings together auctions across a wide range of collecting fields, including coins and medals, stamps and postal history, antiques, art, jewellery, watches, books, wines and spirits, and other collectibles. Visitors can browse current and past auctions, explore catalogues by category, follow upcoming sales, and view unsold lots. Sales take place in several formats, including live, floor, timed, and electronic auctions, with listings from auction houses in multiple countries.

Bid Inside also offers online shops featuring specialist dealers, alongside practical resources for collectors such as registration guidance, bidding information, and frequently asked questions. Users register first through a participating auction house and can then access auctions from other network members with a single login. For auction houses, the network provides a digital channel for presenting sales and reaching collectors, as well as services including the bid-Kit web app and advertising opportunities.