ChessAtlas vs Drop7 Research

A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.

ChessAtlas compared with Drop7 Research
Detail	ChessAtlas	Drop7 Research
What it does	Free chess opening trainer with spaced repetition	Play Drop7 in your browser and follow the open-source search for a million-point strategy.
Stage	Not given	Not given
Founded	Not given	Not given
Based in	Not given	Not given
Pricing model	Freemium	Open source
Pricing	Not given	Not given
Key features	Spaced repetition with FSRS algorithm Repertoire builder Opening trainer with instant feedback Game import from Lichess and Chess.com Deviation detection Course library with opening courses iOS and Android mobile apps Multiple language support	Play Drop7 in browser with interactive board Fourteen different AI strategy approaches Game replay and history tracking Leaderboard competitions Offline gameplay in Classic and Hardcore modes
What makes it different	FSRS algorithm schedules reviews 15-30% more efficiently than SM2 Automatic deviation detection from Lichess and Chess.com games Full repertoire builder in free tier with no course purchase required	Open-source research project with published experiments and reproducible results No ads, purchases, or subscriptions required Play same game as computer strategies for direct comparison
Free plan	Not given	Not given
Open source	Not given	Not given
Platforms	Not given	Not given
Public API	Not given	Not given
Community votes	0	0
DR (Domain Rating by Ahrefs)	10 +1 (up) since last check	5 −1 (down) since last check
Trust Flow (Majestic)	22	6
Citation Flow (Majestic)	24	27
Referring domains (Majestic)	34	46

4 details filled in for both companies.