ATOS Analyzer vs Hemingway Editor

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.

Hemingway Editor scores writing for readability and highlights sentences and issues that may weaken or complicate a message. Editor Plus adds rewriting for wordy sentences and passive voice, grammar fixes, and controls for tone, length and style. It also provides document review with writing feedback and suggestions, and supports importing and exporting Word, Markdown and HTML files. The Classic desktop app works offline and keeps writing on the computer; it can publish to WordPress or export HTML and Markdown for a blogging platform or CMS. Hemingway Editor is available on web, macOS and Windows. The free plan is available. Individual 5K annual access costs $8.33 a month, billed as 100 USD annually, and includes 5,000 AI sentences per month. Hemingway Editor 3 desktop costs $19.99, paid once and does not include new AI features. Hemingway says document content is discarded after processing and is not used to train AI models. For analysis or rewriting, content is sent through Hemingway to an LLM provider, currently OpenAI, Google or Anthropic, and then discarded. Editor Plus does not yet have SOC 2 or ISO certification.