Anki (with AI plugins)
FreeThe gold-standard spaced-repetition flashcard app — now supercharged with AI plugins that auto-generate cards from any text
What is Anki (with AI plugins)?
Anki is the most proven spaced-repetition learning system in the world, used by medical students, language learners, and serious knowledge workers for decades. The core app is free on Mac, Windows, Linux, Android, and web, with a one-time $25 iOS app that funds development. In 2025 and 2026, a wave of AI plugins emerged that dramatically improve the Anki workflow: tools like AnkiBrain, Smart Notes, and the built-in OpenAI plugin use GPT-4-class models to auto-generate cards from PDFs, textbooks, lecture notes, and web articles — turning a 200-page document into hundreds of review-ready cards in minutes. Other AI plugins add image occlusion auto-generation, cloze deletion suggestions, and personalized hint generation that explains why a card is wrong when you miss it. Anki's SM-2 algorithm (and the new FSRS algorithm released in 2024) schedules reviews to maximize long-term retention, meaning you spend minimum time remembering maximum information. Unlike shiny new apps like RemNote or Quizlet, Anki is battle-tested over 20+ years with millions of active users and a huge community deck library (AnkiWeb hosts 100,000+ shared decks, from medical school to language learning to trivia). If you want to learn anything hard and retain it forever, AI-augmented Anki is the most effective and free tool available.
⚡ Quick Verdict
Medical students, language learners, and knowledge workers learning hard material
Casual learners who want polished modern UX out of the box
Free on desktop/Android/web · $25 one-time on iOS
Yes — free on all platforms except iOS
Most effective spaced-repetition algorithm with AI card generation plugins
Steep learning curve and dated UI compared to newer apps like RemNote
Bottom line: Anki (with AI plugins) scores 4.4/5 — the most effective learning tool ever built, now supercharged with AI plugins that turn any document into flashcards in minutes.
Pricing
Anki Desktop (macOS, Windows, Linux): 100% free and open source. Includes the full feature set, card editor, AnkiWeb sync, and support for community plugins including AI-powered card generators.
AnkiDroid (Android): Free on Google Play and F-Droid. Syncs with desktop and AnkiWeb.
Anki for iPhone/iPad: $25 one-time purchase on the App Store. Funds ongoing development of the entire ecosystem. Syncs with desktop and AnkiWeb.
AnkiWeb: Free cloud sync between devices. No subscription.
AI Plugins: Most are free and open source. Paid options like AnkiBrain require OpenAI API keys for generation, which cost around $0.10-1.00 per hundred cards depending on model choice.
Key Features
- Spaced-repetition algorithm (SM-2 and FSRS)
- Sync across macOS, Windows, Linux, iOS, Android, web
- AI plugins that auto-generate cards from PDFs and text
- Image occlusion for anatomy and diagram memorization
- Cloze deletion cards for fill-in-the-blank practice
- Community deck library with 100,000+ shared decks
- Custom card templates with LaTeX math and audio/video
- Open source with 20+ years of active development
Pros & Cons
Pros
- Completely free on all platforms except iOS
- Proven effective by decades of research and millions of users
- AI plugins dramatically reduce card creation time
- Massive community deck library for every subject
Cons
- Desktop UI looks dated compared to modern apps
- Steep learning curve for card formatting and plugins
- iOS app is $25 (though one-time, not subscription)
FAQ
Is Anki really free?
Yes. Anki is free and open source on macOS, Windows, Linux, Android, and the web via AnkiWeb. The only paid version is the iOS app ($25 one-time, not a subscription), which funds development of the entire ecosystem. AI plugins are generally free but often require you to supply an OpenAI or Anthropic API key for generation, which costs a few cents to a few dollars per session depending on volume.
Which AI plugin should I use?
AnkiBrain is the most popular all-purpose AI plugin for auto-generating cards from text and PDFs. Smart Notes is simpler and ideal for beginners. For medical students, MedSchoolGPT and AnkiHub have specialized content. All of these require you to add your own OpenAI or Anthropic API key. The best plugin depends on your subject and learning style — try two or three before settling.
How does AI-augmented Anki compare to RemNote?
RemNote is a newer notes-plus-flashcards app with a polished modern UI and built-in AI features. Anki is 20 years older, uglier, but more flexible, free, and used by the largest spaced-repetition community in the world. RemNote is better if you want an integrated writing + flashcards workflow. Anki is better if you want maximum power, free forever, and access to community decks. Many learners use both.
Is the FSRS algorithm better than SM-2?
Yes, in most cases. FSRS (released in Anki 23.10) uses machine learning on your actual review history to schedule cards more efficiently than SM-2's fixed formula. Users report 20-30% fewer reviews for the same retention. You can switch to FSRS in Anki's deck options. Some purists prefer SM-2 because it is predictable, but FSRS is the recommended default for new decks.
Does Anki sync between devices?
Yes, via AnkiWeb (free). You can review on your phone during a commute, then continue on your desktop at home — progress, scheduling, and new cards sync automatically. AnkiWeb is the official cloud sync and works reliably. No subscription required; it is funded by the $25 iOS app purchase.
Can I share Anki decks with friends or classmates?
Yes. You can export any deck as a .apkg file and share it directly, or upload it to AnkiWeb to make it publicly available to the global community. Many medical schools have class-wide Anki decks maintained by students collaboratively. For private team decks, you can also use AnkiHub (paid) which adds collaborative editing with version control.
📋 Good to know
Download Anki from apps.ankiweb.net, install AnkiBrain or Smart Notes plugin, paste your API key, and drop in a PDF to auto-generate cards.
100% local by default. Cloud sync via AnkiWeb uses encryption in transit. AI plugins send content to third-party LLMs only if you opt in.
Free forever on desktop/Android. $25 iOS purchase if you want to review on iPhone — supports development.
Steep. Plan 2-3 hours to learn basics and card creation. AI plugins reduce long-term card creation effort by 10x but require setup.