Personal chess report

Find out where your blunders really come from.

We check every move of your online games with Stockfish, run a statistical model over all of them, and turn the result into a clear report with a 4-week training plan built from your own mistakes.

Get your free report See a sample

FREE DURING OUR TESTER PHASE · CHESS.COM · EN / DE

Every moveof your last 18 months checked by Stockfish
1 modelclock, phase, position and rating weighed at once
12 slideswith a “how to read” note under every chart
4 weeksof training, targeted at your own patterns

How it works

Your username in, your Blunderprint out.

No software to install, no password, no upload. Your public games are all we need.

Send us your username

Tell us your chess.com username and whether you want the report in English or German.

We analyse every move

Stockfish rates every position of your live games from the last 18 months. A statistical model then shows which situations really make you blunder.

You get your report

A 12-slide report (PowerPoint and PDF) by email, with your key moments on the board and a training plan for the next four weeks.

Sample report

What's inside a Blunderprint

Six of the twelve slides from a real report. Click a slide to enlarge it.

Slide: at a glance – blunders per 100 moves, risk under time pressure, games lost from winning positions — **At a glance**Your blunder rate and the three numbers that matter most.

Slide: the clock – blunders per 100 moves by time left — **The clock**How your blunder rate changes as your time runs out.

Slide: all factors at once – model results as risk multipliers — **What really drives your blunders**All factors in one model, so time trouble isn't confused with hard positions.

Slide: decisive moments – won positions that still slipped — **Decisive moments**How often winning positions slip away, and how often you save lost ones.

Slide: key moments – three boards with the played move and the winning move — **Key moments**Your most expensive misses, on the board, with the move that would have won.

Slide: your next 4 weeks – a training plan in four steps — **Your next 4 weeks**A training plan that follows from your own numbers.

Numbers on these slides come from one real player's games and are shown as an example. Your report uses your own games only.

Why Blunderprint

Not just another engine evaluation

All your games, not a highlight reel

We look at every live game of the last 18 months, not a handful of hand-picked losses. That's what makes the patterns reliable.

One model, all factors at once

Time trouble, game phase, a winning position, a stronger opponent: they often come together. Our model separates them, so you know what really drives your mistakes.

A clear definition of a blunder

A blunder is a move that throws away at least 30 percentage points of winning chances, for example from 70% to 40%. No vague labels.

Made to be understood

Every chart comes with a short “how to read” note. Built by a statistician, checked by a chess player.

Tester phase

Free for our first testers

We're opening Blunderprint to a small group of players. You get your full report for free; in return we'd love your honest feedback.

TESTER PHASE

Full Blunderprint report

Free

In exchange for short feedback after you've read it.

Every move of your live games from the last 18 months
12 slides with the statistical model and your key moments
4-week training plan
English or German, PowerPoint and PDF

Request my report

Coming later

Monthly update

Every four weeks a new report that compares you with your last one: is your blunder rate going down, is the clock effect shrinking?

Lichess support is also on its way.

FAQ

Questions

Which sites do you support?

chess.com for now. Lichess support is in progress.

Do you need my password?

No, never. We only use your public games, which anyone can see on chess.com. Your username is all we need.

Which games are included?

All your live games (bullet, blitz and rapid) from the last 18 months. Daily games and games with fewer than five moves are left out. The more games you have played, the more reliable the patterns.

What exactly counts as a blunder?

A move that loses at least 30 percentage points of winning chances, based on Stockfish's evaluation. In the statistical model, moves from positions below 30% winning chances are left out, because a drop of 30 points is hardly possible there.

What does “2.2× the risk” mean?

It means that in this situation, a move is a little over twice as likely to be a blunder as a normal move – after accounting for all other factors in the model, like game phase, position and your opponent's rating.

How long does it take?

During the tester phase you'll usually get your report within a few days.

What happens to my data?

We use your username and email only to create and send your report. You can ask us to delete your data at any time. Details are in our privacy policy.

Get yours

Request your free Blunderprint

Fill in the form. Your email app will open with a ready-made message – just press send.

No password, no payment
Report by email, usually within a few days
Prefer to write yourself? [email protected]