Is Anki Free? Yes, Except on One Device

Anki is a flashcard app that uses spaced repetition: it shows you hard cards more often and easy ones less often, so you put your time into what you're about to forget. Here's exactly which parts are free, why the iPhone app isn't, and the two AnkiWeb rules worth knowing before you build a big deck.

Which versions of Anki are free

Version	Free?	Who makes it
Anki for Windows, Mac and Linux	Yes, free and open source	Anki's developer
AnkiWeb sync and web study	Yes	Anki's developer
AnkiDroid for Android	Yes	Volunteer contributors
AnkiMobile for iPhone and iPad	No	Anki's developer

Anki's site says AnkiMobile helps fund Anki's development, while AnkiDroid is free, built by contributors and supported by donations.

Why the iPhone app isn't free

Anki's developer explains this in the official FAQ. AnkiMobile isn't meant to be a standalone app. It's designed to work alongside the free computer version and the free sync service, and he describes AnkiMobile as the way he supports himself and funds future work on all three.

Two details help if you're on Apple devices. Once you have AnkiMobile, you can use it on up to 5 of your iOS devices with the same Apple ID, and it supports Family Sharing. So one family can share it rather than each person getting their own copy.

The catch: AnkiWeb deletes inactive data

This is the rule that surprises people. Anki's docs say that because AnkiWeb is a free service, unused account data is deleted periodically to keep it running. If you haven't accessed your account or synced in the last 6 months, the AnkiWeb copy of your cards may be deleted.

Only the AnkiWeb copy goes. Cards stored on your computer, phone or tablet stay on those devices, and your account itself remains. But if your only copy was on AnkiWeb, it can't be recovered. The fix is simple: open ankiweb.net or sync from any Anki app now and then, which marks your account as active.

AnkiWeb size limits

• Collection size: 100 MB compressed and 250 MB uncompressed, covering card text and review history.
• Media: no limit on total media for now, but each media file can be up to 100 MB.
• How far that goes: Anki's docs say 25,000 average cards with several years of reviews take about 25 MB.

Anki says the collection limit can't be raised, because very large collections slow AnkiWeb down for everyone. If you import a huge dictionary-style deck, you'll need to export and remove unused cards to get back under it.

How to start using Anki for free

1. Download Anki for your computer from the official Anki site.
2. Create a free AnkiWeb account so you can sync.
3. Make a deck and add your first cards.
4. On Android, install AnkiDroid and log in with the same AnkiWeb account.
5. Sync at least every few months so AnkiWeb keeps your data.

Free study tips that make Anki work

Anki rewards little and often. Do your reviews daily, keep cards short with one fact each, and use the free add-ons to tweak the layout if you need to. If you want help turning notes into cards, my ChatGPT prompts for exam revision and study plans can draft question and answer pairs for you to check. And if you're comparing flashcard apps, my roundup of Quizlet alternatives covers the main options.

What you get with free Anki

The free version isn't a cut-down edition. Anki's site lists media support for audio, images, video and scientific markup on your cards, custom card layouts and review timing, add-ons for extra features, and decks of more than 100,000 cards without problems. The free AnkiWeb sync keeps it all in step across your computer, phone and the web.

If AnkiWeb has already cleared your data

Anki's docs explain how to recover. Open Anki on your computer or AnkiDroid on your phone and check whether your cards are still there. If they are, log in at ankiweb.net, where you'll see 0 cards, then sync from the device and choose Upload. Anki stresses that you must choose Upload, not Download, because downloading would overwrite your cards with the empty AnkiWeb copy.

If you think you've overwritten your device by mistake, Anki keeps automatic backups you may be able to restore from.

Free Anki on Android vs iPhone

If you're choosing a phone partly for study, this is worth knowing. On Android, AnkiDroid is free and built by volunteers. On iPhone and iPad, AnkiMobile is the official app and it isn't free. Both sync through the same free AnkiWeb account, so you can still study on the web at ankiweb.net if you don't want a phone app at all.

My verdict: Anki is free on computer, Android and the web, and the sync is free too. Only the iPhone app isn't, and it's shareable across your Apple devices. Whatever you use, sync at least every six months so AnkiWeb doesn't clear your data.

Frequently asked questions

Is Anki completely free?

Anki for computers, AnkiDroid for Android and the AnkiWeb sync service are free. AnkiMobile, the official iPhone and iPad app, isn't free.

Why isn't Anki free on iPhone?

Anki's developer says AnkiMobile is how he supports himself and funds work on the free computer version and sync service.

Does AnkiWeb delete your cards?

It can. Anki's docs say AnkiWeb data may be deleted if you haven't accessed your account or synced in the last 6 months. Cards stored on your devices stay there.

How big can an Anki collection be on AnkiWeb?

Anki says collections are limited to 100 MB compressed and 250 MB uncompressed. Individual media files can be up to 100 MB.

Can I share AnkiMobile with my family?

Yes. Anki says AnkiMobile works on up to 5 of your iOS devices with the same Apple ID, and it supports Family Sharing.

How do I restore Anki after AnkiWeb deleted my data?

If your cards are still on a device, log in at ankiweb.net, sync from that device and choose Upload. Anki says choosing Download would overwrite your cards with the empty copy.