Czech text difficulty checker
Paste any Czech text here — a news article, a recipe, a song lyric, a paragraph from a novel — and Beeblio will break it down by word frequency. Each word is assigned to a band based on how common it is in real Czech: the 300 most frequent words, then up to 800, 1,500, 3,000, and beyond. Words you're likely to know light up in one colour; rarer words stand out in another, so you can see at a glance how much of the text is within reach.
This is especially useful for finding texts at the right level of challenge. A good comprehensible-input text is one where most words are already familiar and only a handful are new. The checker shows you exactly that split: what percentage of the text falls inside each frequency band, which specific words are new to your level, and which are genuinely rare even for advanced learners.
Frequency ranks come from the wordfreq corpus, which draws on a wide range of real Czech text. Just paste, check, and decide whether a text is worth reading today — or better saved for later.
How it works
Paste a text in Czech (up to 6,000 characters). Every word is looked up in a frequency list; for each band — the top 300, 800, 1,500, 3,000, 5,000, 8,000 and 12,000 words — you see the share of the text a learner at that band already knows. Comprehensible reading sits around 95–98% known: we call ≥97% easy, 92–97% just right, 85–92% hard, and below that too hard.
You also get the new words worth learning (unknown but common, in frequency order) and the rare words — names, jargon, typos — that no learner should stop for.
Questions
What do the frequency bands mean?
Beeblio divides Czech vocabulary into bands based on how often words appear in real text: the first band covers the 300 most frequent words, then 800, 1,500, 3,000, 5,000, 8,000, and 12,000. Knowing the most frequent 1,500 words puts you in reach of roughly 80% of everyday Czech, so the bands give you a practical sense of how much work each new word is worth.
Which word forms does the checker recognise?
The checker works with lemmas — the base form of each word — so inflected Czech forms like "dělám", "dělá", and "dělali" all count towards the same frequency rank as the lemma "dělat". This means you won't be penalised for natural grammatical variation in the text.
How do I use this to pick the right Czech text to read?
Aim for texts where the vast majority of words fall within a band you're comfortable with, and only a small number are new or rare. If a text flags dozens of unfamiliar words across several bands, it's probably too difficult for comfortable reading practice right now — save it and come back when your vocabulary has grown.