Browser-native · No install · Local-first

Prep smarter. Play sharper.

Search 10.4 million games by position, scout any opponent before round one, and drill the lines that matter — the whole prep loop in one browser tab.

Open FlexiChess — No account needed

FlexiChess Game View workbench reviewing a Kasparov game with Stockfish lines at depth 18, game review scores, eval graph, and the game search dock — A real Kasparov game under review — move classifications, Stockfish lines, Pallas coach notes, eval graph, and database search in one workbench.

Local-first storageOn your device first, backed up to your account

Stockfish 18Deep multi-line analysis, in your browser

10.4 million games indexedSearchable in seconds

Verified coachReplayed and checked, never guessed

Database search

Search 10.4 million games, club to world championship

Drop in any position and see who's reached it — and how they played on from there.

Finds the position however it arose — transpositions included, not just one move order
Real games stream in as each one is verified, right in your browser
Ranked by player strength — the strongest games first

exact-position match · transpositions included

10.4M+games indexed by position

every game that reached it, strongest first — matches stream in as they're verified

Game search

Search by idea, not just position

Type what you're after in plain English — “Najdorf middlegames where White won with an isolated queen pawn” — or build it with a precise, ChessBase-style filter. Same engine either way: it finds the games that match, by structure, endgame, opening, tactics, players, or result.

Plain English or a structured mask — your choice, one engine behind both
Filter by pawn structure, endgame, opening, tactics, players, result, Elo
Tells you what it understood — and what it couldn't. No silent guessing.

FlexiChess Game Search — a natural-language query parsed into Kasparov and exchange-sacrifice chips with 95 matching games listed by opening, result, and event — One search bar for everything — drop in a player, colour, opening and idea, type it in plain English, or open the board and filters to build a precise query.

Scout

Pro

Scout your opponent before round one

Name any player or paste their games and Scout builds the prep automatically — their opening tendencies, how they score line by line, and the gaps where they've got nothing prepared. Walk in knowing exactly what to aim at.

FlexiChess Scout report on a database player — prep-split verdict, openings where they underperform, best-scoring weapons to avoid, and a board ranking their first moves by how well they score — Scouting a database player — repertoire score bars and the key positions they keep reaching.

AI coach

A coach that's checked, not guessed

Ask Pallas anything about the position in front of you — who's better, what to play, why a move went wrong — and it answers in plain language. Every move and tactic it names is replayed against Stockfish before you see it, so you get grounded guidance, not a confident-sounding guess.

Ask in plain English on any position — the verdict, the plan, and the point of a move
The moves and tactics it cites are engine-checked before they're shown — marked with an “Engine-backed” badge
Free to try on every game; Pro raises the weekly allowance for daily prep

FlexiChess Pallas coach panel on a live Kasparov–Adams position — a plain-language verdict ('Black is worse; 35…Rc7 is the only way to stay in the game') with concrete lines, an Engine-backed badge, and one-tap follow-up questions — Pallas reading a live Kasparov–Adams position — a plain-language verdict with concrete lines, and the “Engine-backed” badge marking that the tactics were checked against Stockfish first.

Workbench

Built like desktop software. In a browser tab.

Everything open at once — board, database, engine, coach — laid out the way you actually think through a position.

Classic stacked cockpit or freeform floating windows on large screens
Layout presets: Opening prep, Live viewing, Analysis, and custom workbenches
Resize and rearrange panels without leaving the browser

FlexiChess opening explorer — the board beside the move list and the explorer table ranking every reply by frequency, with popularity trend and the white/draw/black split from millions of games — The opening explorer — every reply ranked by frequency, with the win/draw/loss split from millions of games, in one workbench panel.

Your openings, in long-term memory

Spaced repetition drills your own lines on a real board — the same memory science as flashcards, playing the moves instead of flipping cards. Free for everyone.

FlexiChess repertoire builder — pick your reply at each position with its win/draw/loss split, see the gaps you haven't covered ranked by popularity and rising trend, coverage at 100%, with the Pallas coach alongside — Build your repertoire — pick a reply at each position, with opening stats and Pallas alongside — then drill it with spaced repetition.

Your games. Your machine. Your data.

Your games live in your browser first — instant, and they work offline — then back up to your account automatically so they're on every device. Local-first, never cloud-only. Sign in (free) to build a library; turn backup off anytime.

Diagram: your library lives in your browser while signed out; when you sign in it backs up to your personal cloud database automatically — Stored on your device first, backed up to your account. Privacy policy →

Simple, honest pricing

One tool instead of a database, a trainer, and a coach.

Pro: $14/mo · $109/yr (save 35%) · Cancel anytime

Free

Free to explore — sign in (free) to import & save.

Engine analysis, eval graph & move classification — no account
10.4M+ game database — position search, no account
Structure search — find games by any position-type (IQP, rook endings, …), no account
Opening book explorer — no account
Import your own PGN/FEN games (free account)
FSRS repertoire training (free account)
Free account: automatic backup + cross-device sync, 50,000-game cloud library
Pallas, your AI coach — 1 a day, or 15 a week with a free account
Pallas game narration — annotated critical moments, 3 games a week with a free account
Scout opponents — 8 reports a month with a free account

Recommended

Pro

$14/mo

Everything in Free — at ceilings built for daily prep.

Everything in Free, with the allowances multiplied (all ceilings published in Help)
Deep structure search — stack position-types (IQP + rook ending + …) and search the full result set
Opponent scouting — up to 1,000 reports a month (Free: 8)
Pallas AI coach — up to 300 questions a week · game narration up to 100 games a week
Cloud library up to 5,000,000 games, synced across all your devices
Cancel anytime · fair use

Billed monthly · or $109/yr saves 35%

Try free Sign in for sync