This depends entirely on the child, as well as on their background, intelligence, curiosity and natural reading ability, not to mention the child's parents. I learnt to read at home before I started school (which was at 4 years old, pretty young!), so in terms of reading I was well ahead of most other kids my age. I think I could probably have read these kinds of books at age 5 or 6 (particularly the early ones). Most kids would probably need to be a bit older though, ranging from about 4 or 5 in rare cases up to 11 or 12, or even higher. I would put the average at around 8 or 9 years old.

Hm, my sister and I started reading the books when we were young. We were... maybe 7 or 8 years old, I believe. The first few books are quite easy to read; the last few books in the series are bigger and have darker themes, so I think that would be the main thing to keep in mind.

If the child is a good reader, then probably about 10 years old.

I would guess around 10 years old children begin to read books... but Harry Potter is a long book (series) - so I'd say maybe 12 years old. Of course everyone enjoys the HP movies / even little kids - who aren't reading longer books yet. 좋은 질문이었어.

I know that your question is about english spoken countries but I would like to comment even if my answer is topic out. In France, I think that children can start Harry Potter when they are 10 or 11 for the good reader. I have pupils who are 6 and 7 and none of them are ready to read this kind of book (they just start to learn how to read for the 6 years old.) Even the first book is long for a little child. That was my topic out's answer. Sorry