Getting the most from jam1e chess

Quick start

Most people arrive with one question: what is the best move here? This is the fastest way to answer it.

1. Open the board.
2. Get your position onto the board. Play the moves from the start, paste a FEN, or tap the pencil icon under the board to place pieces by hand.
3. Set White to move or Black to move at the top of the panel. This matters: the best move for White and for Black are completely different.
4. Read the answer. The best move appears in large type, with a blue arrow on the board and the evaluation on the right.

Setting up a position

Tap the pencil icon under the board to enter the editor. You will see a palette with every piece, a hand and a bin.

• Place pieces: pick a piece in the palette, then tap squares. Tapping a square that already holds that piece removes it, so you can toggle quickly.
• Move pieces: pick the hand, then drag pieces around. Drag a piece off the board to delete it.
• Delete pieces: pick the bin and tap the pieces you want gone.
• Starting position and Clear board give you a quick reset. Clear leaves just the two kings.
• Castling rights: tick the boxes only if that king and rook have not moved yet. If you are not sure, leave them unticked.
• When you press Done the position is checked. If something is impossible, for example a pawn on the first rank or the side not to move standing in check, you will see a short message telling you what to fix.

Reading the best move

The analysis card shows three things.

• Best move in standard notation, with a plain-English line under it such as Knight g1 → f3 so you never have to decode the notation.
• Evaluation, such as +1.35. Positive numbers favour White, negative numbers favour Black. Roughly, one point is worth one pawn. +M4 means White can force checkmate in four moves.
• Top lines. The three best moves, each with the sequence the engine expects to follow. Click a line to play its first move on the board.

The thinking time buttons control how long the engine searches: Fast (about one second), Strong (about three), Deep (about nine) or unlimited. Longer is stronger, but even Fast is far stronger than any human. The thin blue bar shows progress, and the depth figure tells you how many moves ahead the engine has looked.

The vertical bar beside the board is the evaluation bar. The more white it shows, the better White is doing.

For many well-known positions the answer appears instantly, labelled Lichess cloud. That is a deep analysis already stored on Lichess's servers. Your own engine keeps running in the background and takes over once it has searched deeper.

Read Reading an engine like a pro for more on what the numbers mean.

Moving through a game

• Use the arrow buttons under the board, or the ← → keys. ↑ jumps to the start and ↓ to the end.
• Click any move in the move list to jump to it.
• If you go back and play a different move, the game continues from there. In review mode your new moves are kept as a side line, so the original game is never lost.
• Press F or the flip icon to see the board from Black's side.
• Right-click and drag to draw your own arrows. Right-click a square to highlight it. Left-click anywhere to clear them.

Opening names and book moves

As you play from the starting position, the Opening card names the opening you are in, for example Sicilian Defense: Najdorf Variation, using the open Lichess opening list of more than 3,000 named lines. It also lists the book moves from the current position. Click one to play it. The number beside each move is how many named variations continue through it, a rough guide to how main-line it is.

Endgame tablebase

When seven or fewer pieces are left (kings included), a Tablebase card appears. A tablebase is not an estimate: it is a complete solution, so White wins really means that White wins with perfect play. It lists every good move with how long the win takes. This comes from the Lichess tablebase service.

Playing the computer

Open the Play tab, choose a level from 1 to 10 and a colour, and press Start game. Levels 1 to 4 play deliberately loose moves for beginners. Levels 5 to 9 aim at a rating, from about 1400 up to grandmaster strength. Level 10 is full-strength Stockfish and is not meant to be beaten.

• Hint draws a green arrow for the best move.
• Take back undoes your last move and the engine's reply.
• When the game ends, Review this game sends it straight to the review tool.

Reviewing a game

Open the Review tab and either paste a PGN or import a recent game. For imports, choose Lichess or Chess.com, type a username and press Fetch. Pick a game from the list and the review starts.

Every position is analysed in turn. When it is done you get:

• Accuracy for each player, from 0 to 100. It measures how much winning chance each move gave away, so 90+ is excellent and below 70 means some costly errors.
• A count of ?! inaccuracies, ? mistakes and ?? blunders.
• An evaluation graph. White area means White is better. Red and orange dots mark the big errors. Click the graph to jump to that moment.
• Tags on every move in the list, and under the board a note telling you what the best move was and a link to show it.

Quick takes about a third of a second per position, Standard about a second, Deep about two and a half. A 40-move game on Standard takes around a minute.

Scanning a board from a screenshot

Open the Scan tab, then drop a screenshot, click to pick a file, or simply paste an image with Ctrl V (⌘ V on a Mac) anywhere on the page.

The scanner looks for the 8×8 grid, works out which squares hold pieces, and matches each piece's shape. It runs entirely in your browser. Then:

1. Check the board. Squares the scanner was unsure about are outlined in orange. Fix any mistakes with the editor.
2. Choose who is to move.
3. Press Analyse this position.

Sharing and saving

• The link icon copies a web address for the exact position and moves on the board. Anyone who opens it sees the same thing.
• Copy FEN copies the current position. Copy PGN copies the moves played so far.
• The palette icon changes the board colours: Slate, Walnut, Mint, Graphite or Midnight. Your choice, level and settings are remembered on this device.

Keyboard shortcuts

Privacy and fair play

The engine runs on your own device, so positions you analyse are not sent to us. To fetch cloud evaluations, tablebase results and imported games, the position or username is sent to Lichess or Chess.com, just as it would be on their own sites.

Please do not use the engine during a game you are playing against a person, online or over the board. It is against the rules of every chess site and federation, and it takes away the very thing that makes chess fun. Use it afterwards, to learn.