Lichess
Chess.com
Chess Tempo Database
DecodeChess
itch.io
Chessable
Aimchess
ChessDB
RepDB
RepDB is a one-time-purchase exercise dataset for developers building fitness and workout apps โ not a subscription, not a rate-limited API. You download the data once and own it: JSON (and SQLite on the higher tier), WebP images, and full EN/DE/ES translations, with no per-request billing and no dependency on our servers staying up.
A free tier includes 250 exercises with flat-style 512ร512 images, attribution-licensed for commercial in-app use. The Starter tier ($199) adds the full catalog in classic white-background style. Standard ($399) adds transparent 1024px images, looping animations, exercise relations (similar/progressions/regressions), workout templates, and embeddings โ exclusive to that tier.
Every exercise includes muscle-group highlighting, equipment/muscle icons, MET values, and safety/goal tags. Compared to GIF- or JPG-based competitor APIs, RepDB images are transparent WebP with no watermarks, so they drop into any app UI without a white box around them.
Lichess RepDBRepDB's answer:
RepDB is sold as a one-time download, not a metered API โ you own the JSON/SQLite data and WebP images outright, with no rate limits, no per-request billing, and no risk of the vendor cutting off access. It's also the only dataset in this space with EN/DE/ES translations, transparent (alpha-channel) images with no watermark, muscle-group highlighting, safety/goal tags, and looping animations on the higher tier.
RepDB's answer:
RepDB grew out of a consumer workout app its creator was building solo. Sourcing exercise images and data meant either paying for a subscription API with usage caps and no caching rights, or producing everything from scratch. The illustrated, multi-language dataset was built for us first, then split out as its own product once it became clear other indie developers had the same problem and preferred to buy the data outright rather than rent it through an API.
RepDB's answer:
Most alternatives are subscription APIs โ you pay monthly, you're capped on requests, and ExerciseDB's terms of use explicitly forbid caching or storing the data at all, so every image render is a live paid API call. RepDB is the opposite: pay once, download the files, self-host with zero ongoing dependency. It's also the only option offering true DE/ES localization and transparent images instead of a white box behind every exercise.
RepDB's answer:
Solo developers and small teams building fitness or workout-tracking apps (iOS, Android, web) who need licensed exercise images and structured exercise data, but don't want to build their own media pipeline or depend on a rate-limited third-party API.
Based on our record, Lichess seems to be more popular. It has been mentiond 922 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Hi HN! I build this project to explore an idea I got in mind for a long time : Is transformer a suitable architecture for a chess bot? I built a small model (11M parameters) and trained it on human games (Elite Lichess DB). Model alone is performing around 1500 elo, but I built an harness using Monte Carlos Tree Search (MCTS) using my model heuristics to improve the model to ~2100 elo (evaluated against... - Source: Hacker News / 2 months ago
Lichess is incredibly well optimized [0] (and an amazing public service). I'm sure that this is very cost effective for TTT, so a win-win. [0] https://lichess.org/@/revoof/blog/optimizing-the-tablebase-server/MetV0ZQd. - Source: Hacker News / 5 months ago
Https://lichess.org/@/Lichess/blog/lichess-and-take-take-take-sign-cooperation-agreement/DZS0S0Dy. - Source: Hacker News / 5 months ago
The actual blogpost: https://lichess.org/@/Lichess/blog/op1-partial-8-piece-tablebase-available/1ptPBDpC On a related note, anyone knows a Mastodon proxy that doesn't require JS and I can just pipe links through? - Source: Hacker News / 7 months ago
Lichess uses a scheme which is probably more efficient on average, described on revoof's blog[0]. Basically, it's a variable length scheme where the first 64 bits encode square occupancies, followed by piece codes (including castling, side to move, and ep with some trickery), followed by half-move clocks if necessary. 0:... - Source: Hacker News / 8 months ago
Chess.com - Play chess on Chess.com
Chess Tempo Database - Chess Tempo Database gives you a library of more than 2 million searchable chess games.
DecodeChess - AI chess tutor and analysis
itch.io - An online game marketplace and community.
Chessable - Chessable uses science-based training techniques to improve how you learn content from chess books and videos.
Aimchess - Learn chess your way with AI tools and data driven approach.
