Free AI Content Detector — No Signup, No Limits
Instantly detect whether any text was written by AI (ChatGPT, GPT-4, GPT-5, Gemini, Claude, LLaMA) or a human. Transparent sentence-level analysis with perplexity and burstiness scores — completely free, forever.
How Our Free AI Content Detector Works
Three simple steps — no account, no credit card, no waiting.
Paste Your Text
Copy and paste any content — blog posts, essays, emails, product descriptions, academic papers, or social media captions — into the text box above. No word limit.
Click Analyse
Our algorithm examines four key metrics — perplexity, burstiness, sentence uniformity, and vocabulary richness — across every single sentence in your text.
Review Transparent Results
Get an overall AI probability score, sentence-level colour-coded highlighting, and full metric breakdowns. Download or copy your report instantly — no paywall.
What Our AI Detector Analyses — Full Transparency
Unlike black-box tools, we show you exactly how we score your text.
Perplexity Score
Perplexity measures how predictable the word choices are. AI-generated text tends to choose the most statistically likely next word, resulting in low perplexity. Human writing is more varied and surprising, producing higher perplexity scores.
Burstiness Score
Burstiness measures variation in sentence length and complexity. Humans naturally write with high burstiness — mixing short punchy sentences with longer complex ones. AI produces uniformly structured sentences with low burstiness.
Sentence Uniformity
We measure how similar your sentences are in length and structure. AI models tend to generate sentences within a narrow length range (15–25 words). Human writers are more inconsistent — and that inconsistency is a strong authenticity signal.
Vocabulary Richness
We calculate the ratio of unique words to total words. AI often recycles the same vocabulary throughout a piece, while humans draw from a broader lexicon. Higher vocabulary richness typically indicates human authorship.
Why Choose BrightlyFuture AI Detector Over GPTZero, Originality.ai & Copyleaks
Built to fix the biggest frustrations with existing AI detectors.
Truly Free — No Hidden Limits
Unlike GPTZero (800 words/scan free) and Originality.ai (no free plan at all), our detector is 100% free with no word caps, no daily limits, and no credit system. Ever.
No Signup Required
GPTZero and Originality.ai both require account creation. We believe privacy starts with anonymity — paste your text and analyse immediately without registering.
Sentence-Level Highlighting
Every sentence is individually scored and colour-coded (red = likely AI, yellow = uncertain, unmarked = human) so you can pinpoint exactly which parts need rewriting.
Transparent Scoring Metrics
Copyleaks hides its scoring methodology. We show you every metric — perplexity, burstiness, uniformity, and vocabulary richness — so you understand why your text was flagged.
100% Private & Secure
GPTZero, Originality.ai, and Copyleaks all store your text on their servers. Our detector runs entirely in your browser — your content is never uploaded, stored, or shared.
Multi-Model Detection
Detects patterns from ChatGPT (GPT-3.5, GPT-4, GPT-4o, GPT-5), Google Gemini, Anthropic Claude, Meta LLaMA, Mistral, DeepSeek, and other large language models.
BrightlyFuture vs GPTZero vs Originality.ai vs Copyleaks — Honest Comparison
We researched every major AI detector so you can compare fairly.
| Feature | BrightlyFuture | GPTZero | Originality.ai | Copyleaks |
|---|---|---|---|---|
| Free to Use | ✓ Unlimited | Limited (800 words) | ✗ No free plan | Limited (10 pages/mo) |
| No Signup Required | ✓ | ✗ | ✗ | ✓ (limited) |
| Sentence-Level Highlighting | ✓ | ✓ | ✓ | ✓ |
| Perplexity & Burstiness Shown | ✓ | Partial | ✗ | ✗ |
| Multi-Language Support | ✓ | Limited | ✓ (30 langs) | ✓ (30+ langs) |
| Data Privacy (No Storage) | ✓ Browser-only | ✗ Server-stored | ✗ Server-stored | ✗ Server-stored |
| Free Downloadable Reports | ✓ | Paid only | Paid only | Paid only |
| Unlimited Scans | ✓ | ✗ (10/day free) | ✗ (credit-based) | ✗ (credit-based) |
| No Credit Card Needed | ✓ | ✓ | ✗ | ✓ |
Who Uses Our AI Content Detector?
Built for anyone who values content authenticity and transparency.
Teachers & Educators
Screen student submissions for AI-generated content before grading. Unlike GPTZero, our tool is free for unlimited student papers.
Content Managers & Editors
Verify freelancer deliverables, guest posts, and contributed articles before publishing to maintain editorial standards.
SEO Professionals
Check whether content meets Google’s E-E-A-T guidelines. Identify AI-heavy sections that could hurt search rankings.
Recruiters & HR Teams
Verify cover letters, writing samples, and application essays for authenticity during the hiring process.
Publishers & Authors
Maintain editorial integrity by screening manuscripts, articles, and submitted content before publication.
Bloggers & Copywriters
Self-check AI-assisted drafts before publishing. See exactly which sentences flag as AI and rewrite them to sound natural.
Tips for Getting the Most Accurate AI Detection Results
Follow these best practices for reliable analysis.
Use at Least 50 Words — 150+ for Best Accuracy
Short snippets lack enough statistical signal for reliable analysis. Independent tests confirm that all AI detectors — including GPTZero and Copyleaks — perform significantly better on longer text samples.
Test Full Paragraphs, Not Bullet Points
Sentence fragments, bullet lists, and headings can skew detection results. Use complete paragraphs with natural sentence structure for the most accurate analysis.
Analyse Different Sections Separately
In long documents, different sections may have different authors or AI involvement. Test the introduction, body paragraphs, and conclusion separately for granular insight into each section.
No AI Detector Is 100% Accurate
Independent benchmarks show even top tools like GPTZero score 62–88% accuracy, and Copyleaks around 79%. Use AI detection as one signal alongside your own editorial judgement — never as the sole basis for consequential decisions.
Watch for Paraphrased AI Content
Text run through paraphrasing tools can fool most detectors — Copyleaks accuracy drops by 50% on humanised text. If you suspect paraphrasing, look for unnatural phrasing and vocabulary inconsistencies alongside our scores.
More Free AI Tools from BrightlyFuture
Explore our growing library of free content and marketing tools.
AI Blog Generator
Generate SEO-optimised, human-sounding blog posts in 30 seconds. No signup, no credit card, unlimited use.
Try Free →AI Paraphraser / Rewriter
Rewrite paragraphs to sound more natural, improve readability, and make AI-assisted content undetectable.
Try Free →Word & Character Counter
Count words, characters, sentences, paragraphs, and estimate reading time for SEO-optimal content length.
Try Free →Frequently Asked Questions About AI Content Detection
Everything you need to know about detecting AI-generated text.
Yes — completely free with no hidden costs, no trial period, no credit system, and no upgrade prompts. Unlike Originality.ai (which has no free plan) and GPTZero (which limits free users to 800 words per scan), every feature on BrightlyFuture — including sentence-level analysis and downloadable reports — is free forever.
No signup, no email, no account required. Both GPTZero and Originality.ai require account creation before you can scan any text. BrightlyFuture lets you paste your text and get results immediately — no registration needed.
Our detector analyses patterns from all major large language models including ChatGPT (GPT-3.5, GPT-4, GPT-4o, GPT-5), Google Gemini, Anthropic Claude, Meta LLaMA, Mistral, DeepSeek, and other popular LLMs. The analysis focuses on writing patterns common across AI models rather than model-specific signatures.
Perplexity measures how predictable word choices are in a text. AI models choose the most statistically probable next word, producing low perplexity. Human writing is more creative and unpredictable, resulting in higher perplexity. GPTZero uses this metric too — we show it transparently so you can understand exactly why your text was scored the way it was.
Burstiness measures the variation in sentence length and complexity throughout a text. Humans naturally write with high burstiness — mixing short sentences with longer ones, varying complexity paragraph to paragraph. AI tends to produce uniformly structured sentences with consistent length, resulting in low burstiness scores.
No. Unlike GPTZero, Originality.ai, and Copyleaks — which all upload and process your text on their servers — our analysis runs entirely in your browser using JavaScript. Your text is never uploaded, stored, logged, or shared with any third party. Complete privacy by design.
We recommend at least 50 words for a basic scan and 150+ words for the most accurate results. This aligns with industry findings — all major detectors including GPTZero and Copyleaks perform better on longer samples. Very short texts (under 30 words) may not contain enough patterns for reliable detection.
Paraphrasing tools can reduce detection accuracy across all detectors — Copyleaks accuracy drops by roughly 50% on humanised text, and similar drops affect GPTZero and Originality.ai. Our detector still catches many AI patterns that survive paraphrasing (such as sentence uniformity and vocabulary distribution), but results may show as “mixed” rather than definitive.
We believe in honesty: no AI detector is 100% accurate. Independent benchmarks show GPTZero at 62–88% accuracy (despite claiming 99%), Copyleaks at ~79%, and Originality.ai with 2–5x higher false positives than competitors. Our detector uses the same proven metrics (perplexity, burstiness) and adds vocabulary richness analysis — use results as a strong signal, not absolute proof.
Yes — our detector works across English, Spanish, French, German, Hindi, Urdu, Arabic, Portuguese, and more. Detection accuracy is highest for English (as with all AI detectors), but the underlying metrics — sentence structure, vocabulary distribution, and burstiness — transfer well across languages.
Absolutely — this is one of the most popular use cases. Paste your AI-assisted draft, see exactly which sentences flag as AI (highlighted in red), then rewrite those specific sections to sound more natural before publishing. The sentence-level analysis makes this targeted editing much faster than rewriting blindly.
Google’s official policy states that AI content is acceptable if it provides value, is accurate, and demonstrates E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness). However, mass-produced AI content without human review can hurt rankings. Use our detector to identify weak sections, add your expertise and personal experience, and ensure your content reads as genuinely valuable.
No limits whatsoever. Analyse one text or one thousand — there are no daily caps, no word limits, no throttling, and no credit system. GPTZero limits free users to ~10 scans per day and 10,000 words per month. Originality.ai charges per 100 words scanned. We have no such restrictions.
Yes — use the Copy Report button to copy a detailed text summary to your clipboard, or Download Report to save a .txt file with the full analysis including verdict, metric scores, sentence-by-sentence breakdown, and statistics. Both features are completely free — competitors like GPTZero lock report downloads behind paid plans.
Plagiarism checkers compare your text against existing published content to find copied passages. AI detectors analyse writing patterns — perplexity, burstiness, sentence structure — to determine whether the text was generated by an AI model, even if the content is completely original and appears nowhere else online. They solve different problems and are most effective when used together.
Is Your Content Written by AI?
Find out in seconds — free, private, and transparent. No signup, no limits, no hidden costs.
🕵 Analyse Your Text Now — 100% Free