About BidCalc
BidCalc is a free set of auction fee calculators and plain-English guides. It shows what an auction purchase or sale really costs once the buyer's premium, VAT, fees and delivery are added, before you bid.
What you'll find here
- The auction fee calculator for buyers, with a "maximum bid from your budget" mode, currency conversion and a resale profit estimate
- The Copart UK calculator, with Copart UK's published fee tables built in
- A fee comparison tool and a seller's net proceeds calculator
- 24 auction guides, and a directory of 79 UK auction houses with maps and contact details
Who it's for
People buying or selling at UK auctions: first-time bidders, collectors, dealers and resellers, vehicle buyers, and anyone bidding from abroad. It's built around one problem: the winning bid isn't the price you pay.
Where the numbers come from
- Fees and VAT. You enter the percentages from the auction's conditions of sale, so every result is based on your own figures. BidCalc doesn't know any auction house's fees, apart from Copart UK's, which come from its published fee schedule as of September 2026.
- Exchange rates. Live reference rates from a free public service. They're a guide, not the rate your bank or card will charge.
- Auction house details. Compiled from publicly available listings in October 2026. They can change, so check with the auction house.
- Guides. The worked examples are checked against the calculators, and where the law or HMRC guidance is involved, the guide points to the source.
What BidCalc doesn't do
It isn't tax, legal or financial advice, and it can't guarantee that a figure will match your invoice. Fees, VAT treatment and terms vary between auction houses and lots, so always confirm with the auction house before you bid.
Independence and how the site is funded
BidCalc is independent. It isn't affiliated with, endorsed by or paid by Copart or any of the auction houses listed on the site. The site is free to use. It may carry affiliate links from time to time (for example to eBay through the eBay Partner Network). These are always marked as adverts and never change a calculation.
Your privacy
There are no accounts, and nothing you type into a calculator is sent to us. Your list of lots stays in your own browser. Read the privacy policy for the details.
Contact
Email us
For questions, feedback, corrections or listings, email info@bidcalc.co.uk. We aim to reply within a few working days.
Email info@bidcalc.co.ukReport an error
Fees and addresses change. If something on BidCalc is wrong, email us the page address, what's wrong, and a link to the official source if you have one, and we'll look into it.
Missing or out-of-date auction house
Send the name, address, phone number and website. If you run an auction house and your details are wrong, or you'd like to be added or removed, email us and we'll update the listing. Listings are free and aren't endorsements.
Last reviewed October 2026.