How to play

Guess the hammer price of one car a day.

  • One live Bring a Trailer auction, no reserve, so it will sell.
  • One sealed guess. No changes after midnight ET.
  • Research all you like. The listing is a click away; the comments are the game.
  • The hammer falls about a week later. Your score lands in the book.

Examples

Say the car sells for $27,100.

  1. $26,0004% low · 94 pts
    Within 5% is a bullseye.
  2. $30,40012% high · 84 pts
    Off by 12% still scores well.
  3. $54,2002x high · 0 pts
    Double (or half) the hammer scores nothing.

Scoring is by ratio, so a $12k Miata and a $700k Ferrari play the same. Your streak counts days you guessed, not days you were right.

Sign in to keep your book across devices. No account needed to play.
A new car is posted every day. Guessing closes at midnight Eastern.

Glossary

Borrowed from the saleroom. Bring a Trailer is a silent countdown; we brought the auctioneer.

Going once
The auctioneer's first call. You commit a number, then wait for the hammer.
Hammer
The final price. Every car here is no reserve, so the hammer always falls.
The book
Where a bidder's commitments are recorded. Your pending and settled guesses.
Paddle number
Your number in the room. It is your handle here; no name needed.
Knocked down
Sold. A guess is scored the moment its car is knocked down.
Fair warning
The last call before the hammer. Here: under an hour until guessing closes.
The crowd
Everyone else's guesses on the same car, shown once the window locks.
Bullseye
Within 5% of the hammer.
Sleeper
A car that blows past what the crowd expected.
White glove
A sale where every lot sells. A perfect week of bullseyes.
Going Once
 

Privacy

Last updated September 2026.

What we store

A random device token in a cookie, so your guesses come back to you on the same browser. Your guesses and their scores. If you sign in, your email address, used only to send you the sign-in link and, later, your results.

What we do not do

No advertising, no selling or sharing of your data. We count page views with Vercel Analytics, which uses no cookies and stores no personal data. We do not read your guesses for any purpose other than scoring them and showing the crowd once a window locks.

Bring a Trailer

Car photos and listing details are Bring a Trailer’s and are loaded from their servers. Following a listing link takes you to their site, under their policies.

Your choices

Clear the cookie and you are a new player. Sign out and this device forgets your book. Email hello@goingonce.io to have your account deleted.