I am new to Anki. I saw that there were Spanish learning decks from other users which are just what I need. I downloaded two of them on my computer but when I tried to sync them for use on my iPad I found that they were too big. So my question is how do I remove cards from the more difficult end of the deck and how can I estimate how many cards need to be removed.
Not sure what you mean by “too big”, but if this is just about file size, media files probably contribute the bulk of it. You can use suitable external tools to reduce their sizes.
Too big is vague. If you mean the amount of cards in a deck looks too intimidating like the many “top [big number] words in X language” decks then I wouldn’t be worried. There are many ways to filter a big deck to what you need. If you mean the file size is too big then there’s quite a lot of options depending on the situation. Some details would help narrow down what you need. For example, what is limiting your space (ipad storage, Anki server, etc.), what deck(s) has this issue (one with images, video, audio or chunks of web code) and how do you want to decide what cards to remove if it comes to that.
If you’re very short on space, and willing to remove part of the deck, you can order the cards by a desired column in the Browse screen of the computer version, delete the unwanted ones, and then use Tools>Check Media to remove any associated media files (which will be where the majority of the space is consumed).
To clarify the decks I first downloaded were too large for the sync with my mobile devices. There appears to be a limit of 100mb on the size of a deck which can be synced. I tried deleting half the cards on the extensive deck I first tried but still got the same messages on trying to sync with my iPad. I deleted the deck and instead downloaded a smaller deck which works fine. Just a pity the very comprehensive deck I first tried cannot be used in this way. Perhaps it would be good if generous contributors were advised to keep their decks down to the sync limit by splitting them into Part 1, Part 2, etc. Thanks anyway for the various suggestions.
Indeed, there is a limit of 100 MB for collections on Ankiweb. However, since this doesn’t take into account media files, it’s very unusual for a deck to exceed this limit. 100 MB in raw text is enough to fill a small library.
Deck text can balloon out in size when the fields contain a lot of (often superfluous) HTML formatting. What was the exact error message you got @102jgl102?