Nayr's Core5000 deck (Frequency Dictionary of Japanese)

You will notice that he scanned the the kanji in the "word" field, not the "expression" field, so that number is only a representation of the 5000 individual words, not the 5000 sentences as a whole.


That being said, you would be surprised on how few kanji are actually used in native media.

There was an interesting article written here: http://pomax.nihongoresources.com/index....1223039457

Basically:
Here's the list of how many kanji you need to know in order to have covered which percentage of kanji-use (on average) in about 1300 novels:

up to 10%: 11 kanji
up to 20%: 20 more kanji: 31
up to 30%: 33 more kanji: 64
up to 40%: 50 more kanji: 114
up to 50%: 74 more kanji: 188
up to 60%: 103 more kanji: 291
up to 70%: 148 more kanji: 439
up to 80%: 222 more kanji: 661
up to 90%: 348 more kanji: 1045