Learn anything. Remember it for years. Not just until tomorrow.
Books, articles, courses. Space quizzes you right before you'd forget, so what you learn actually stays.
Free on iOS, Android, Mac, Windows, Linux. 5 min a day.
The attention economy made you forget. Retrieval gets it back.
The bottleneck isn't input. It's retention.
You already consume enough. The attention economy made sure of that. The problem is that almost none of it compounds.
The feed trained you to forget.
The attention tax
Every platform on your phone optimizes for engagement, not memory. The habit is contagious: you start skimming books and articles the same way you scroll reels. Input goes up. Retention goes to zero.
Your notes app is a graveyard.
Capture ≠ retention
Highlighting, bookmarking, saving for later: it feels productive because it runs on the same dopamine loop as scrolling. None of it rewires memory. Passive storage gives you the illusion of knowing without the substance.
AI compounds daily. Your memory doesn't.
The asymmetry problem
Every model ships with more capability than the last. Your recall, judgment, and expertise stagnate inside an attention economy built to keep you scrolling past everything you meant to keep.
Built on decades of cognitive science.
Two techniques. 1,000+ studies. An algorithm tuned to your memory, not to your attention.
Active Recall
Every retrieval strengthens the neural pathway. Space forces retrieval. The single most effective learning technique ever measured.
Instead of re-reading, you actively reconstruct knowledge from memory. Each successful retrieval makes the next one easier and more durable.
Spaced Repetition
Review at the precise moment before you forget. Not sooner. Not later. The timing is everything.
Spacing reviews at increasing intervals creates permanent memory with minimum effort. The optimal schedule is different for every piece of knowledge.
Illustration coming soon
FSRS-6 Algorithm
The most advanced open-source spaced repetition scheduler. It models your personal forgetting curve and optimizes every interval.
Peer-reviewed research shows FSRS-6 predicts recall more accurately than SM-2, the algorithm Anki has used since 1987. It adapts to your individual memory patterns, so every review is precisely timed.
Illustration coming soon
From reading to retention in 30 seconds
Space's AI extracts the structure from any document: paste, upload, snap. You review. The algorithm does the rest.
Instant Extraction
Paste a URL, upload a PDF, snap a page. AI identifies the key concepts and generates a structured knowledge set in seconds.
Screenshot coming soon
Contextual Explanations
Stuck on a concept during review? Get an instant, context-aware explanation without leaving your session.
Screenshot coming soon
Deep Exploration
Go beyond surface-level recall. Ask follow-up questions, explore connections, build genuine understanding.
Screenshot coming soon
Engineered for serious learners.
Every feature exists because it makes your learning more effective. Nothing more.
FSRS-6 Scheduling
Calculates optimal review timing for every card. Adapts to your memory. Zero configuration.
AI Knowledge Extraction
URL, PDF, or text in. Structured knowledge out. Seconds, not hours.
Cross-Platform Sync
iOS, Android, macOS, Windows, Linux. Real-time sync. Pick up where you left off.
Universal Import
Anki, CSV, Excel, Google Sheets. Bring your existing knowledge. Zero lock-in.
Rich Content
Images, audio, code blocks, LaTeX, drawings. Some knowledge can't be reduced to text.
Offline-First
Full functionality without connectivity. Sync resumes automatically.
Your knowledge pipeline.
Three stages. One system. Compounding returns.
Ingest
Feed Space anything worth remembering. A URL, a document, a lecture. AI extracts the structure.
Review
FSRS-6 schedules precision-timed reviews. 5–15 minutes daily. The algorithm handles the rest.
Compound
Knowledge builds on knowledge. Over weeks and months, what you review crystallizes into retrievable expertise.
Other apps compete for your attention.
Space builds your memory.
vs. Note-taking apps
Notion, Obsidian, Roam capture information. Space makes you remember it. Capture without retrieval is storage, not learning.
- No retrieval practice built in
- No intelligent scheduling
- No forgetting curve awareness
vs. Legacy tools
Anki pioneered spaced repetition. Space modernizes it: FSRS-6 over SM-2, native AI, real-time sync across 5 platforms, and a UI that belongs on a modern phone.
- More advanced algorithm (FSRS-6)
- AI-powered knowledge extraction
- Native on every platform
vs. No system
Most professionals have no retention strategy. They rely on re-reading, bookmarks, and hope. Space replaces hope with science.
- 5 min/day is all it takes
- Algorithm handles scheduling
- Knowledge compounds automatically
Trusted by professionals who take learning seriously.
"This is one of those apps that I remember installing when I buy a new phone. Also, beautiful app."
— App Store Review
"Exceptional Spaced Repetition app! 1000x better than your old friend Anki."
— App Store Review
"The best flashcard app I have ever used. The FSRS algorithm is incredibly effective for long-term retention."
— Google Play Review
"Finally a spaced repetition app that works on all my devices and looks great doing it."
— Mac App Store Review
Frequently asked questions
Is this just a flashcard app?
How is this different from taking notes?
How much time does this take?
Is it free?
What is FSRS-6?
Can I import existing material?
What platforms are supported?
What does Space Pro include?
Your knowledge, compounding.
Free on every platform. No credit card required.
