Acid Ape Chess

Acid Ape Chess is the multi-purpose chess suite aimed at the serious player.

Acid Ape Chess is organized with a tools philosophy in mind. You can leverage its modular design to perform common and less common chess-related tasks.

Acid Ape Chess focuses on:

• quality;
• elegance;
• ergonomics;
• versatility.

Some Acid Ape Chess features:

Online chess

• Play on FICS, ICC and Lichess
• Watch live online games
• View online players and their game history
• Non-disruptive in-game chat using a subwindow at the bottom of the chessboard

Chess engines

• Play against UCI or CECP chess engines
• Organize engine duels
• 3 strong builtin engines are provided (Arasan, cheng4 and Scorpio)
• Use third-party engines
• Adjust engine-specific settings
• Use custom PolyGlot (.bin) and Arena (.abk) opening books
• Use custom neural networks

Analysis

• Analyze with multiple chess engines
• Display the principal variation and stats
• Display an evaluation graph
• Display Syzygy 7-men EGTB results (uses an online service)
• Easily create, annotate and move variations with our move list editor
• Automatic analysis (apply the best move every x seconds)
• Auto annotate games using a chess engine and the endgame tablebases
• Advanced move indicators displaying engine evaluation scores

Premium access to our online database

• 260 million positions
• 4.5 million games, from the 1800s to 2025
• 330,000 OTB players, from club players to superstars
• Used by the opening explorer
• Can be used as an opening book for chess engines
• Search for players, display games, filter by ELO and opening
• Our database is updated continuously
• The perfect tools for your game preparation

PGN support

• Your played games are autosaved
• The PGN Explorer: a file manager with PGN support
• Edit your games (headers, move tree, annotations)
• Load and save PGN files
• Clipboard support
• Share your games as PGN download links

OTB chess

• Watch live games from major professional tournaments
• Search our online database for players and games
• Use a stylish fullscreen clock for your OTB games
• Play OTP (over the phone): two players on the same phone or tablet.

Electronic boards and clocks

• Drivers for the DGT Bluetooth e-Board, the DGT USB e-Board, the DGT Smart Board, the DGT Revelation II, the DGT3000 and the DGT Pi
• Play online, engine and OTB games with your physical board and clock
• Connect via Bluetooth or USB

Blindfold play

• The board and move list are hidden
• You input your moves via speech recognition
• Opponent moves are announced via speech synthesis

Tactical puzzles

• Solve 900 puzzles split into 3 levels of difficulty
• Import your own PGN puzzles

Simuls

• Challenge from 2 to 16 engine opponents
• Play blindfold simuls

A comprehensive user manual

• Explains everything about AAC, and more!
• Presented as a book, accessible from AAC
• Contains numerous use cases and tips

Extra features

• Play Chess960
• Choose from many different board and piece themes
• Enter local player details, with country flag, chess title and ELO
• Use the position editor to encode positions for playing or analysis
• Move speech recognition and synthesis
• A LCD chess clock modeled after real hardware, with sound and flag display
• Displays your personal statistics against your opponent
• Use a standalone clock app for your non-connected OTB games

This is Acid Ape Chess Standard Edition, which only provides a subset of the listed features. For the full set, see Acid Ape Chess Grandmaster Edition.

Recent changes:
- A Lichess protocol change broke challenges: fixed.
- Miscellaneous fixes and improvements.