100%Free,Unlimited,Instant,No-Login,Private,Deep&AccurateAIDetector.

A free, private AI content detector built by Ceptile to provide transparent, inspectable forensics for text, images, video, and audio. Paste text or drop any file into the AI detector or AI checker below to analyze 46 open stylometric signals, C2PA provenance, and sensor physics — 100% on-device with zero server uploads.

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Free AI detector guide

The free AI detector for text, images, video, audio & essays

What is an AI detector and how does an AI checker work?

An AI detector — also commonly searched as an AI checker or AI detector tool — is an analytical system designed to evaluate whether content was composed by a human or generated by large language models such as ChatGPT, GPT-4, GPT-5, Claude, Gemini, Llama, or Grok. When you need to AI detect machine generation, our platform analyzes statistical signals including lexical dispersion, burstiness, Zipfian distribution fits, and syntactic entropy. Unlike proprietary black boxes that return a single arbitrary score, this transparent AI detector by Ceptile calculates 46 open signals and displays the exact mathematical weight of each feature. Users seeking the best AI detector experience can audit every calculation without subscription paywalls or hidden parameters.

Free AI detector online: multi-modal detection across all media

As an AI detector free online, this platform provides unlimited scans across text, images, video, and audio. Unlike competing services that gate features behind credits, our free AI detector and AI detector free platform requires no account registration, no email signup, and imposes no daily limit. Everything executes locally on your device via client-side WebAssembly and modern browser APIs. When you run a free AI checker or AI checker free scan, your confidential files never leave your computer, ensuring absolute privacy for sensitive manuscripts, legal briefs, and student coursework.

AI detector text, human checker, and essay AI checker for academic integrity

Educators and academic institutions face significant challenges with uncredited generative text. Our specialized AI checker for teachers and AI detector for essays provides an objective, transparent framework for evaluating student submissions. When conducting an essay AI checker assessment, our dedicated AI detector text and AI checker text engine parses sentence-level perplexity variance and flags synthetic discourse markers. To ensure fairness, our system includes an ESL-safe calibration mode that prevents non-native English writers from being penalized for formal sentence structures. Furthermore, authors and researchers can use this platform as an objective human checker to verify and prove authentic human writing against false accusations. We recommend educators use this ai detect text capability as an exploratory conversational aid rather than punitive evidence.

AI detector for images: inspecting C2PA, EXIF, and camera sensor physics

The proliferation of synthetic media requires robust visual forensic tools. The AI detector for images and AI detector for photos pipeline deploys a two-tier verification architecture. Tier 1 examines provenance metadata, including Coalition for Content Provenance and Authenticity (C2PA) cryptographic credentials, EXIF headers, and generation parameters embedded by Midjourney, DALL-E, Stable Diffusion, and Flux. When metadata has been stripped by social networks, Tier 2 analyzes pixel-level sensor physics. Physical cameras exhibit high-frequency sensor noise across color filter arrays, whereas diffusion models exhibit unnaturally high cross-channel correlation. This enables our AI detector image, AI detector photo, and AI checker image suite to AI detect image synthesis on original uncompressed media with verifiable precision.

AI detector for video: temporal grain and generative motion dynamics

With text-to-video generators like Sora, Google Veo, Runway Gen-3, Pika, Kling, and Hailuo producing photorealistic sequences, video verification has become critical. The AI detector for video and AI detector video module inspects MP4, WebM, and MOV containers for cryptographic provenance. Sampled video frames are then decoded in your browser tab to measure temporal consistency, optical flow vectors, and inter-frame shot noise stability. While real cameras produce continuous temporal photon shot noise, synthetic engines frequently suffer from micro-flicker and unnatural phase shifts. This makes our AI checker video and AI detect video workflow indispensable for journalists and fact-checkers investigating synthetic footage.

AI detector for audio, voice, song, and music verification

Voice cloning and synthetic music have expanded dramatically across podcasts and streaming platforms. Our high-resolution AI detector for audio and AI detector audio suite enables users to AI detect voice clones, deepfake speech, and synthetic audio clips without uploading sensitive audio to cloud servers. Operating as an advanced AI checker audio, the system decodes WAV, MP3, FLAC, and OGG streams directly in memory. It applies spectral centroid analysis, spectral flatness, and bispectral quadratic phase coupling to uncover vocoder artifacts characteristic of ElevenLabs, Bark, and OpenAI voice engines. Furthermore, listeners and music producers can easily AI detect song tracks and AI detect music compositions generated by Suno, Udio, and related generative models. Use our dedicated acoustic tab to AI detect audio patterns in real time.

The Ceptile intelligence ecosystem: AI search and verifiable attribution

Developed by Ceptile (ceptile.com), the creators of next-generation search and intelligence platforms, this forensic engine represents a core component of the broader Ceptile AI ecosystem. Ceptile is pioneering intelligent information retrieval through Ceptile AI search, Ceptile web search, Ceptile search, and Ceptile AI web search technologies designed to deliver transparent, verifiable answers. In an era where web search and generative AI are converging, the Ceptile AI detector and Ceptile AI checker provide the authoritative attribution standard required to separate authentic human scholarship from machine-generated approximations. You can always trust an AI checker by Ceptile to deliver objective, private, and mathematically verifiable results.

How to AI detect free in three simple steps

Screening content with our free AI detector takes only seconds. First, select your media category and paste text into the input box or drag and drop a file into the photo, video, or audio analyzer. Second, select your desired sensitivity calibration and click Analyse to AI detect free. Third, examine your composite AI-likelihood score alongside its 90% confidence interval, sentence-by-sentence heatmap, and forensic diagnostic table. You can then instantly export comprehensive reports in PDF, Markdown, JSON, CSV, or HTML format for documentation or classroom review. For privacy details see our no-upload privacy guarantee; for responsible classroom use read the teacher ethics checklist.

Why this AI checker

Six things the big AI detectors will not do.

We looked hard at ZeroGPT, QuillBot and GPTZero before building this free AI detector. They are good products. These are the gaps we decided to close.

Every number, shown

Other AI detectors give you a percentage and a brand name for their black box. We print all 46 signals: the measured value, the calibration centres, the z-score, the separation statistic, the fitted coefficient, and the exact contribution each one made to the score. You can redo the arithmetic yourself.

Nothing is uploaded

The whole AI detector tool is JavaScript that runs in your tab. Your draft, your students’ essays, your client’s unpublished manuscript — none of it reaches a server, because there is no server to reach. Load the page, then turn off your Wi-Fi and it still works.

Honest about what it cannot do

We publish our false-positive rate by genre, we widen the interval on short text instead of guessing, and we say “inconclusive” when the evidence is inconclusive. A confident wrong answer is worse than an honest uncertain one when somebody’s grade depends on it.

Hard evidence, not just vibes

Zero-width characters, curly quotes and NBSPs pasted straight out of a chat window, assistant scaffolding phrases, chat-export markdown, duplicated sentences. These are facts about the file, reported separately from the statistical score.

Real image forensics

C2PA Content Credentials, EXIF, PNG text chunks and Stable Diffusion parameter blocks first. Then capture physics: a camera builds each colour channel from different sensor sites, so their high-frequency residuals disagree. A diffusion decoder paints all three from one latent, so they match. That single measurement separates the classes by d = 1.35.

Production video forensics

MP4, WebM, MOV and MKV parsed for Sora, Veo, Runway, Pika, Kling and C2PA provenance, then sampled frames measured for sensor physics plus temporal grain, flicker coherence and optical-flow motion — with identical JSON, Markdown, CSV, HTML and PDF reports.

Production audio forensics

WAV, MP3, FLAC, OGG and M4A decoded on-device. Spectral shape, bispectral vocoder artefacts and temporal voice dynamics measured and fused with the exact arithmetic shown — a screening signal, never fake proof.

No account, no cap, no paywall

No sign-up, no character limit, no credits, no “upgrade to see highlights”. Sentence-level detail and full JSON, Markdown and PDF export are part of the free product, because a report you cannot show to anyone is not a report.

Best AI detector comparison

Free AI detector vs ZeroGPT, QuillBot & GPTZero.

Competitor capabilities as advertised on their own marketing pages at the time of writing. We have not copied anyone's interface, and we are not claiming to beat them on raw model accuracy — we are claiming that an auditable score you can check is worth more than an unauditable one you cannot.

	AI Detector by Ceptile	ZeroGPT	QuillBot	GPTZero
Where analysis runs	Your browser	Their servers	Their servers	Their servers
Free character limit	None	15,000	~1,200 words	10,000
Account required	No	For reports	For history	For most features
Shows the maths	All 46 signals	No	Explainer cards	No
Publishes false-positive rate by genre	Yes	Headline figure only	Headline figure only	Headline figure only
Confidence interval on the score	Yes	No	No	No
Says “inconclusive”	Yes	Rarely	Leans human	Rarely
Sentence-level detail free	Yes	Yes	Yes	Partly
Export report free	JSON, MD, PDF	Paid	Paid	Paid
Shareable report link	Free, reproduces the exact score	Paid / account	No	Dashboard only
Document upload (PDF, DOCX, TXT)	Free, parsed on-device	Yes	Yes	Yes
Batch scoring with CSV export	Free, on-device	Dashboard upload	No	Classroom plans
Private local history	Free, this browser only	Account dashboard	Projects (account)	Dashboard (account)
Writing-process provenance	Local typing/paste log	No	No	Cloud video replay
Originality assist + web-search checks	Free, on-device	Paid checker	Paid checker	Paid checker
Revision guidance tied to fired signals	Free	Humanizer (paid)	Humanizer (paid)	AI tutor (paid)
Image forensics	Yes, on-device	Separate tool	No	No
Video AI detection	Yes — frames + temporal, on-device	No	No	No
Audio AI detection	Yes — spectral + bispectral, on-device	No	No	No
Publishes image-tier miss rate	Yes — full table by file condition	No	n/a	n/a
Works offline	Yes	No	No	No

Free AI checker questions

Straight answers about this AI detector.

Is this AI detector really free?

Yes. This is a free AI detector with no account, no character limit and no paywall. You can AI detect text, check essays and run the AI detector for images as many times as you like. Sentence highlights and report export are included in the free AI checker — unlike ZeroGPT, GPTZero or QuillBot, where reports and history sit behind paid plans.

How accurate is this AI checker?

Under five-fold cross-validation on 2,743 real documents — 1,153 human texts across ten genres and 1,590 real machine outputs (ChatGPT plus a dozen other models), all truncated to the same length — the text engine reaches an ROC AUC of 0.966, with 90.5% accuracy, 88.1% recall and a 6.2% false-positive rate at the 60% decision point we ship (4.6% at 70%, where recall is 84.0%). The percentage is a calibrated probability, not a rescaled score: Brier 0.069, expected calibration error 2.1 points. An earlier calibration on hand-written imitations scored 0.989 against the imitations and below chance against real model output, so the imitations were discarded; these numbers are lower and honest. The accuracy page explains exactly how they were produced and where they will be optimistic.

Can teachers use this AI checker for essays and student work?

Yes — this AI checker for teachers is one of its most common uses. Paste an essay to AI detect text, read the sentence-level map, and check which signals fired before talking to the student. Because analysis runs on-device, student work is never uploaded, which avoids the data-protection problems of server-side essay AI checkers. Never use any AI detector score as the sole basis for an academic penalty.

Does the AI detector work on images and photos?

Yes. The AI detector for images and AI detector for photos inspects C2PA Content Credentials, EXIF, PNG text chunks and Stable Diffusion blocks first, then falls back to pixel physics such as cross-channel residual agreement. On original files it cleared 29 of 29 photographs and caught 14 of 14 generated images. On recompressed social-media JPEGs it honestly returns inconclusive — see the measured numbers.

Does the AI detector work on video?

Yes — the AI video detector parses MP4, WebM, MOV and MKV containers for Sora, Veo, Runway, Pika, Kling and C2PA provenance, then samples decoded frames for sensor physics plus temporal grain, flicker and motion coherence. Every frame measurement and the exact score arithmetic are printed, with free JSON, Markdown, CSV, HTML and PDF export. Short or recompressed clips honestly return low reliability instead of a fake confident number.

Does the AI detector work on audio and voice?

Yes — the AI audio detector decodes WAV, MP3, FLAC, OGG and M4A locally with no upload, then measures spectral shape, bispectral vocoder artefacts and temporal voice dynamics. The report shows every measured value with its centres, LLR, weight and contribution plus the exact logit formula. Under one second of audio returns low reliability by design.

Why is there no AI model behind this AI detector?

Because a detector built on a neural network cannot tell you why it decided anything, cannot run on your machine, and cannot be audited by the person whose work it just accused. Everything here is closed-form statistics: entropy estimates, Zipf and Heaps fits, Jensen–Shannon divergence, bootstrap intervals, Fourier transforms. Same input, same output, every single time.

Can it be fooled by paraphrased AI text?

Yes, and so can every other AI detector, including GPTZero, Originality.ai and ZeroGPT. Running generated text through a paraphraser, asking for a specific voice, or editing heavily will all pull the score down — sometimes a long way down. Our contribution is to show you which signals moved, so you can see whether a text looks human or merely looks laundered.

Will it flag a non-native English speaker?

Less than an AI detector tuned on perplexity alone, which is the specific failure mode documented in the literature — simpler, more predictable English reads as machine-written to those tools. Our strongest signals are lexical distribution rather than raw predictability, and we deliberately hold the prior on the human side. But the risk is real, it is not zero, and it is why the interface reports an interval and a reliability grade instead of a single confident number.

Do you store what I paste in the free AI checker?

We cannot. There is no backend, no database, no analytics script and no telemetry in the page. Open your browser’s network tab while you run a free AI check: after the page loads, it stays empty.

A product of Ceptile

Part of the Ceptile ecosystem.

AI Detector by Ceptile (aidetector.ceptile.com) is built by Ceptile, founded by Shaurya Agarwal to bring verifiable, local-first research tools to the web. Both Ceptile and this detector share the same premise: inspectable citations and math over opaque black boxes.

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A score is evidence. It is not proof.

No AI detector — ours, theirs, anyone's — should be the sole basis for an academic penalty or an employment decision. Use AI Detector by Ceptile to decide where to look and what to ask about. Then talk to the person.

Read the limits