Tone Analyzer - Sentiment, Formality & Confidence Checker

Free Tone Analyzer — Sentiment & Formality

Analyze sentiment, formality, and confidence of your writing with tone keywords. Runs in your browser.

Sentiment scoring

AFINN-based sentiment score from -5 to +5 with an overall tone label like Professional or Casual.

Formality & confidence

Separate scores for how formal and how confident your writing sounds.

Browser-only analysis

The AFINN lexicon runs locally — no API calls, no data sent anywhere.

Frequently Asked Questions

Everything you need to know about tone analyzer.

Yes, completely free with no account required and no usage limits.

No. All analysis runs directly in your browser using JavaScript. Your text never leaves your device.

It uses the AFINN-165 lexicon — a peer-reviewed word list where each English word is rated from -5 (very negative) to +5 (very positive). Your text's score is the sum of all matched words, normalized for length.

It combines your sentiment, formality, and confidence scores into a single descriptor: Professional, Academic, Persuasive, Emotional, Casual, Assertive, Uncertain, or Neutral.

English only. The AFINN lexicon and the formality and confidence word lists are all tuned for English text.

No — sarcasm requires deep contextual understanding beyond word-level analysis. The scores reflect the literal meaning of the words used.

No hard limit. The analysis is synchronous JavaScript and handles long documents quickly in any modern browser.