Thirty words, from A1 to C2, about three minutes. Pick the right meaning or say you do not know, and get your CEFR level and an estimate of how many words you know. 27 languages, free, no sign-up.
Watch Your Language groups its packs by the same CEFR levels as this test. Start at the band you found, and the app shows those words on your iPhone Lock Screen and Apple Watch face, bringing back the ones you keep forgetting.