A chess coach in your inbox · every week
Stop making the same?? mistake twice.
Blunder Brief runs every game you played this week through Stockfish, works out why you lost points, and sends you a coach's report with drills from your own positions.
First 2 reports free, no card needed. Then $0.99 a month or $10 a year.
How it works
Connect once. Improve every week.
Link your accounts
Add your Chess.com username or connect Lichess. We only read your public games, never your password.
We analyse every move
Stockfish checks each position, then sorts your mistakes the way a coach would: missed tactics, ignored threats, bad trades, endgame slips.
Your weekly report
A short, human-sounding email with your week, your losses, one focus to work on, and five drills on an interactive board.
Inside the report
Written like a coach. Not a spreadsheet.
Every section is built from your own games. Here's what a week looks like for a 1650 rapid player.
A strong week
7 games: 6 wins and 1 loss. Rating 1635 → 1681 +46
What went well
- You came back from a losing position and didn't lose.
- Your openings are working: +1.9 on average by move 12.
What to tighten up
- One winning position slipped away (reached +2, didn't win).
- Blunders are up: 1.9 per game, against 1.1 before.
Sample content for illustration. Your report uses your own games.
What you get
Everything a coach would point out.
Drills from your games
Five positions a week where you had something better. Play your move on the board, then reveal the answer. No engine bar to give it away.
Loss autopsy
For every loss: the first slip, and the move that decided it. Short enough to read over coffee.
Repertoire check
Flags lines where you keep coming out of the opening worse, and the exact move where it went wrong.
One focus at a time
We pick the error costing you most, set a target, and only move on once your last 10 games prove it's fixed.
Puzzles that fit
Links to puzzle themes matching the patterns you missed this week: forks, skewers, hanging pieces, rook endgames.
Clock habits
Spots whether your errors come from rushing or from long thinks that end in the wrong move.
Pricing
Cheaper than one blunder.
Try two reports free. Keep going for less than a coffee a month.
Free trial
- Full weekly report
- Five drills each week
- Chess.com and Lichess
- No card needed
Blunder Brief Pro
- A report every week
- Drill archive of every week
- Training focus that adapts
- Cancel any time
Questions
Before you castle.
Do you need my Chess.com or Lichess password?
No. Chess.com games are public, so a username is enough. Lichess uses its own sign-in page, and we only check which account is yours.
Which games do you analyse?
Rated games in the time controls you choose. Rapid by default; you can add blitz or classical. Bullet is too noisy to coach from.
What happens after my 2 free reports?
Your next report arrives as a preview with a link to subscribe. Nothing is charged automatically, because we never asked for a card.
How is this different from the analysis button?
Engine analysis tells you what the best move was. Blunder Brief tells you why you missed it, how often that kind of mistake costs you, and what to practise this week.
Can I cancel?
Any time, from your account page. You keep receiving reports until the end of the period you paid for.