It’s not perfect, but ichi.moe is pretty good about this as long as the entire word is written in hiragana. It tends to fail pretty hard at the half-kanji, half-kana sentences you might encounter still.
Though on the flip side, it’s probably not a bad idea to start working on being able to recognize words when written in kana, as a non-trivial number of the words you learn here will generally only be written in kana and if you plan to take the JLPT you will also encounter a non-trivial amount of words that won’t be written in kanji in the lower levels.
Plus depending on the target audience of native material, sometimes the authors will use kana instead of kanji if it’s assumed that the audience hasn’t yet learned that kanji. You’ll see this a lot in manga especially those that are targeted to student-aged readers and depending on at what age they will learn certain kanji.