Language-model similarity
A small open model compares the passage with patterns learned from human and AI-generated text.
Free · private · no sign-up
Free AI Detector
Check whether a passage contains patterns often associated with AI-generated text. Get one clear 0–100 score, passage-level signals, and honest limits—without uploading your writing.
✓ Always free✓ Text stays in your browser✓ No account required
TEXT SAMPLE
Paste the writing you want to check
✓Your text stays in this browser. The model downloads to your device; the draft is not uploaded or saved.
Read the score carefully
A signal for review.
Never a verdict.
The free AI checker compares the writing with patterns learned from both human and generated text. It also looks at rhythm and repetition. The final number describes similarity—not who wrote it.
- 0–29Low AI signal
Fewer learned AI-writing patterns appear in the sample.
- 30–59Mixed signal
The detector sees competing or inconclusive evidence.
- 60–79Elevated signal
Several patterns resemble generated writing.
- 80–100High AI signal
Strong similarity—but still not proof of authorship.
What this free AI detector checks
One model. Three useful lenses.
The result combines a compact language model with simple writing-pattern checks. That makes the score easier to inspect, but it cannot replace source history or human judgment.
Rhythm and variation
Sentence-length changes and structural variation add context to the model reading.
Phrase-level review
The strongest passages are surfaced so you can review the writing instead of trusting one opaque number.
Built for a careful first pass
Free to check.
Responsible by design.
An AI content detector can misread polished human work, heavily edited AI text, translations, formulaic academic writing, or very short samples. Use the result to ask better questions—not to make automatic accusations.
- Use at least 80 words when possible.
- Compare the original source and revision history.
- Never treat a score as standalone evidence.
Questions, answered
Free AI text detection,
without false certainty.
Is the UltraHumanizer AI detector free?+
Yes. The text detector is free to use, requires no account, and does not charge for checks. The compact detection model runs in your browser.
Does the AI text detector upload or save my writing?+
No. The page downloads the detection model and analyzes the text locally in your browser. Your draft is not sent to UltraHumanizer or written to its database.
Can an AI detector be 100% accurate?+
No. AI text detectors can produce false positives and false negatives, especially with short, edited, technical, or multilingual writing. A score should guide review, not prove authorship.
How much text should I check?+
For a more useful reading, paste at least 80 words. Longer samples give the detector more rhythm, repetition, and phrasing patterns to compare.