Most free AI detectors hand you a single percentage and hope you do not ask where it came from. TextSight Free runs the same classifier Pro runs, surfaces sentence-level evidence on every scan, and keeps the result page clear of ads. Three scans a day at 5,000 characters each, no card and no email required for your first scan, and the same ESL calibration that drops false positives by about 40 percent versus uncalibrated detectors. Accuracy on the free tier matches paid tiers within rounding because there is no separate free-tier model. Only the daily quota differs.
Three scans a day, 5,000 characters per scan, and the full evidence panel. The numbers below are exactly what you get on the free tier with no upgrade gate.
Resets on a rolling daily window. Three scans cover the most common cases the free tier serves: a pre-submission essay check, a freelance deliverable review, and a quick sanity pass on a short article. Heavier daily volume is the line where free moves into Starter or Pro, but it is also the line where ad-funded free clones start to break.
Roughly 800 words. Long enough to cover most essays, blog posts, and product descriptions in a single scan. Documents over 5,000 characters can be split into sections, or run through the higher per-scan cap on Pro at 10,000 characters. The free per-scan cap is a real cap, not a teaser-grade quota that hides the actual usable text length.
Green for human, yellow for borderline, red for AI. Every sentence carries the specific signals that triggered its colour, so a global score is always paired with the underlying evidence. This is the feature most free competitors gate behind paid plans, and the reason their free percentages feel unactionable.
Returned alongside the Authenticity Score on the same scan. A simple flag highlighting passages with a higher chance of overlap against indexed sources. Not a full plagiarism report (that lives in the Plagiarism tool), but enough to know whether the AI score is the only thing worth thinking about for a given piece.
There is no quiet downgrade on the free tier. The classifier, the calibration, and the scoring scale all match the paid tiers within rounding. Only the daily quota differs.
On unedited model output of 500 words or longer, the classifier sits at roughly 89 percent across mixed model families (GPT-4, GPT-4o, GPT-5, Claude 3, Claude 3.5, Gemini 1.5, Gemini 2.0, Llama 3). Long-form is where detection has the most statistical signal to work with, and where the published number is most reliable.
Mid-length text (200 to 500 words) lands at roughly 82 percent. Short text under 200 words drops to roughly 75 percent because there is simply not enough statistical signal for any classifier in the category to land confidently. The result panel surfaces a low-confidence flag on short text so you know to treat the score as suggestive rather than precise.
Uncalibrated detectors typically score 8 to 12 percent false positives on ESL writing because simpler vocabulary and more uniform sentence structure overlap with how language models write. A calibration layer trained on roughly 600,000 ESL samples drops the rate to 4 to 6 percent. Native English false positives stay at 1 to 2 percent, the industry norm for the band. ESL calibration is on by default on the free tier.
Any tool advertising 99 or 100 percent is quoting a best-case test set, not real-world performance. Treat the Authenticity Score as a calibrated signal, not a verdict. Pair it with the sentence-level highlights to see which paragraphs are driving the result, then make an editorial call from there. This page does not promise anything that detection cannot deliver.
Three scans a day on free, unlimited on Pro. The classifier and the sentence-level evidence are identical. Yearly billing saves 25%.
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The free tier is designed so a single scan runs end to end in about thirty seconds on an 800-word essay, with no signup gate before your first result.
Open app.textsight.ai. Paste up to 5,000 characters into the detector tab. The character counter ticks as you type or paste, and no signup is required before your first scan. Three scans a day means you can run three independent texts through the same workflow before the daily cap applies.
Click Scan. The full classifier runs in roughly six seconds on short text and thirty seconds on an 800-word essay. The result panel returns a 0 to 100 Authenticity Score, the five-band confidence label (Original, Mostly Human, Mixed, Likely AI, AI Generated), and the Plagiarism Risk indicator on the same scan.
Open the per-sentence panel. Every green sentence reads human. Every yellow sentence is borderline. Every red sentence is flagged AI with the specific signals that triggered it listed alongside. The highlights are the evidence that turns a calibrated score into a call you can defend in a conversation with a student, editor, or freelancer.
Use the highlights to edit, escalate, or move on. If the score is borderline and you need more confidence, scan a second draft after editing the red sentences. The free tier is generous enough for genuine pre-submission work, and the upgrade path to Pro is open the moment three scans a day is not enough.
Three structural reasons explain why most of the free results returned by a "free AI detector" search feel unactionable in real use.
Tools funded entirely through ads run lighter classifiers on the free tier because a full transformer per scan costs real money. Lighter classifiers trained on GPT-3.5 era data have not kept up with GPT-4, Claude 3, and Gemini outputs, so the percentage they return is often noise. TextSight keeps the same classifier on free that Pro uses, because the free tier is paid for by Pro subscriptions rather than by the result page itself.
Most free detectors return a single score. A score with no per-sentence colour map tells you the number, not the reason. A 65 percent "AI" reading with no underlying signal is impossible to act on, and that is the experience most "free AI detector" search results deliver. TextSight Free includes sentence-level highlights on every scan because evidence is the difference between a usable score and a number you cannot defend.
Banner ads above the highlights, upsell prompts pasted over the score, interstitial ads when the result loads, and aggressive newsletter modals are standard on ad-funded free detectors. The result page itself is the product they monetize, which is why the actual highlights feel cramped. TextSight Free is funded by paid tiers, not ads, so the result panel stays clean.
Top 6 free-tier tools ranked honestly. Where TextSight wins, where the alternatives are tolerable.
See the ranking →Sentence-level evidence and ESL calibration on the GPT-4 focused detector.
Open the detector →Multi-model detection across GPT, Claude, Gemini, and Llama with the same evidence panel.
Read the page →Full tier breakdown for Free, Starter, Pro, and Business. Annual billing saves 25%.
See pricing →Same classifier as Pro on every free scan, sentence-level highlights included, ESL calibrated. Three scans a day, no card, no email needed for your first scan.