It’s easy. The answer is in your head. Only you know what your level is.
Your reading level depends on what you are trying to do. But first understand there are 4 ‘levels’ of reading.
4 levels of reading
Reading pain: This is when the text is so hard, you spend all your time in the dictionary. You probably understand very little and so you can easily get bored or tired and give up.
Instructional reading: This is a text which is a little difficult, but you understand most of it. Maybe 5-8% of the words and expressions and some of the grammar you don’t know. You’ll probably need your dictionary.
Easy reading: This is a text which is easy to read. You understand all or most of it without problems so you don’t need a dictionary. There may be a few words on the page you don’t know. Your eye moves quickly across the page. Often you don’t even notice you are reading.
Speed Reading: This is a text which you can read very quickly because it’s very easy which allows you to build your reading speed.
Look at this table