Tone Checker
See whether your writing reads formal, confident or critical.
Needs at least 15 words
Tone is measured from word choice, so a short phrase gives nothing to measure.
This counts words, it does not read the room. Tone is estimated by matching your text against lists of words that tend to signal a register. It cannot detect sarcasm, humour, or the context you are writing into, and a text with few signal words will give a weak reading — which the tool says rather than guessing.
Private by design. This tool runs entirely in your browser. Your input is processed on your own device and is not uploaded by DO101.
About the Tone Checker
Estimates the register of your writing by counting the words that signal it, then shows which words drove the reading and what to change to move it towards an essay, a work email or a message to a person. It counts words rather than reading meaning, and the reading is marked weak when there is little to go on.
How to use it
- 1Paste an email, essay, cover letter or message of at least 15 words.
- 2Read the three scales: register, certainty and outlook.
- 3Look at which words drove each reading.
- 4Pick who you are writing for and follow the specific suggestions.
What you get
- Register, certainty and outlook on a two-ended scale each
- The actual words that produced each reading
- Advice tailored to an essay, a work email or a personal message
- Exclamation and question counts, and average sentence length
- Says when the reading is weak instead of inventing a confident answer
Frequently asked questions
How does it work out the tone?
It matches your text against lists of words that tend to signal a register — "furthermore" and "demonstrate" for formal, "stuff" and "kind of" for casual — and reports the balance as a share of the signal words it found.
Can it detect sarcasm?
No. It counts words; it does not read intent or context. Sarcasm, humour and irony will all be scored on their literal wording, which is usually the opposite of what is meant.
Why does it say the reading is weak?
Because it found too few signal words to be worth trusting. That is deliberate — a confident-looking score built on two matched words would be misleading, so the tool says so instead.
Keep going
People who use this tool usually reach for these next.
Catch spelling, grammar, punctuation and wordiness as you type.
Tighten wordy writing with every edit shown and reversible.
Flesch, Gunning Fog, SMOG and three more, with sentence rhythm.
APA, MLA, Harvard, Chicago, IEEE and Vancouver references.