AnchorKite Readability Checker vs ATOS Analyzer

AnchorKite Readability Checker is a free browser tool for evaluating pasted English text. It reports Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog, SMOG, Coleman-Liau, and Automated Readability Index scores. A headline grade estimate averages five grade-level formulas. The page also displays word, sentence, syllable, and letter counts, together with words per sentence and syllables per word. Analysis runs locally, with no network requests, analytics, transmission, storage, or logging of the text according to the page. After loading, the browser tab can continue working offline. Syllable counting uses an approximate heuristic, so irregular spellings and proper names can differ by a syllable. The maker advises treating scores as a sanity check because lists, code, dialogue, headings, abbreviations, and short passages can affect formulas. Guidance covers teachers, writers, workplace writing, general audiences, and specialist writing.

ATOS Analyzer is a free web tool for estimating the readability level of text and books in English or Spanish. Users can enter a passage, analyze an entire book, or submit a sample with an estimated word count. Text can be typed or uploaded as a .txt, .docx, or .epub file, with uploads limited to 10 MB. The suggested passage length is 150 to 25,000 characters. Results include an ATOS level, grade-level equivalent, word count, AR Points, average word length, average sentence length, and language. ATOS estimates complexity on a grade-level scale using sentence length, word length, and word difficulty; its measure also accounts for book length. For a sampled book, Renaissance recommends three passages of about 150 words from different parts and an estimated total word count. Scanned documents need OCR to become recognized text before submission; changing a file extension does not convert them. The page includes a CCSS/ATOS grade-band chart for grades 1 through 12. Renaissance presents the measure as guidance for matching students with appropriately leveled reading material.