AI Detectors.io

AI Detectors.io is a text-analysis service that estimates whether writing is associated with major language models. It provides an overall AI probability, confidence scores, and sentence-level analysis. The company says its detector examines perplexity, burstiness, n-gram patterns, and stylometric fingerprints; its reported 95.2% accuracy and 3.1% false-positive rate come from an April 2026 benchmark of 500 texts. That benchmark covers English, though the service returns scores for other languages. Users can access the service on the web, Windows, macOS, through a Chrome extension, or by API. The Chrome extension analyzes selected webpage text, while a Microsoft Word add-in supports Word 2016 and later on Windows and Mac, as well as Word for the web, and can produce PDF reports. Other tools include a humanizer, citation verification, plagiarism checks, grammar tools, and watermark removal. The free plan includes 10,000 words per month and a 500-word limit per use. Premium costs $8.33/mo billed annually and allows scans up to 25,000 words. Submitted text may be processed by third-party providers.

AI Detectors.io combines AI-text analysis with several writing and verification tools across web, desktop, extension, Word, and API access. Its benchmark and non-English scores have stated coverage limits, and its free plan caps each use at 500 words.

It may suit students, educators, writers, teams, publishers, and editorial staff seeking text analysis or related writing tools. API access and a Word add-in offer options for users working in those environments.

AI Detectors.io is a broad AI-writing analysis service for people who need detection alongside editing and verification tools. It suits students, educators, writers, publishers, and teams that work across browsers, Word, desktop apps, and an API. Its strongest case is a flexible toolkit with detailed sentence-level results; its main caution is that the published benchmark covers English only.

The detector reports an overall AI probability, confidence scores, and sentence-level findings for text associated with major language models. The company says it evaluates perplexity, burstiness, n-gram patterns, and stylometric fingerprints, and also lists paraphrase detection. Those multiple signals can help reviewers investigate suspicious passages rather than rely on a single percentage, but a probability remains an indicator, not proof of authorship.

Overview

AI Detectors.io adds a humanizer, citation verification, plagiarism checking, grammar tools, and watermark removal to its detector. The service reports 95.2% accuracy and a 3.1% false-positive rate from an April 2026 benchmark of 500 texts. That benchmark is English-only; scores are returned for other languages, but the company does not include them in the benchmark coverage, so English results are the only ones supported by the published figures.

Key features

Analysis and companion tools

Sentence-level scoring shows where the system sees likely AI wording, while confidence scores and an overall probability provide a broader assessment. The accompanying humanizer and grammar tools make the product useful for revising flagged passages, and citation, plagiarism, and watermark checks extend it beyond detection. Users seeking only a basic detector may find this breadth unnecessary.

Browser, Word, and API workflows

The Chrome extension analyzes selected webpage text and displays sentence-level results, which is practical for checking online material without copying it into a separate site. The Microsoft Word add-in works with Word 2016 and later on Windows and Mac, plus Word for the web, and can produce PDF reports. The REST API returns an overall AI probability and can provide sentence-level scores. Batch scanning is supported. There are no LMS integrations, limiting direct use inside learning-management systems.

Privacy and support

Submitted text may be processed by third-party AI and infrastructure providers and is retained only as long as needed to deliver and support the operation. The company describes reasonable technical and organizational safeguards but does not promise absolute security. Email support generally responds within one business day, a useful service level for paid users.

Pricing

Free and API entry

The Free plan costs $0 per month forever, includes three signup bonus credits, 10,000 words per month, one free credit daily, and a 500-word-per-use cap. It includes the Basic AI Detector but excludes Ultra mode and tone customization. It is suitable for occasional short checks, not long documents.

Starter (API) is also free, with 100 requests per month and up to 1,000 words per request. It returns an overall AI probability and includes a key dashboard and community support. It is a low-risk way to prototype an integration, but sentence-level API scores require a paid tier.

Paid plans

Premium costs $100 per year, shown as $8.33 per month when billed annually, with two months free (17% off monthly). It raises usage to 500,000 words per month, provides unlimited daily credits, and permits 25,000 words per scan. Advanced AI Detector, Ultra mode, and tone customization make it the sensible choice for frequent individual or editorial use; the annual commitment is the trade-off.

Developer (API) costs $29 per month for 5,000 requests, up to 5,000 words per request, sentence-level scores, and email support. Enterprise has custom pricing and adds unlimited requests, higher rate limits, everything in Developer, and priority support. Neither paid plan has a free trial.

Platforms

AI Detectors.io runs on the web, macOS, and Windows, with Chrome extension, Microsoft Word, and REST API access. Word support spans desktop and web editions, while the extension is specifically for Chrome.

Who it's for

Students and teachers can use the free allowance for short reviews, while writers and editors gain value from sentence-level evidence plus revision and citation tools. Publishers, editorial teams, and software developers are better matched to Premium or Developer API quotas. Organizations needing LMS-native workflows or dependable benchmark evidence for non-English writing should look elsewhere.

Pros and cons

• Pro: Sentence-level findings, confidence scores, and an overall probability give reviewers more context than a single verdict.
• Pro: Chrome, Word, PDF reporting, and API access fit browser, document, and automated workflows.
• Pro: Humanizing, citation, plagiarism, grammar, and watermark tools reduce the need for separate services.
• Con: The free plan limits each use to 500 words and excludes Ultra mode and tone customization.
• Con: Published accuracy and false-positive figures apply only to English benchmark texts.
• Con: Submitted text may pass through third-party providers, and no absolute security guarantee is made.
• Con: No LMS integrations are currently offered.

Alternatives

Choose AI Content Detectors when you want a broader directory comparison before selecting a service.

TrustOriginality.ai is a better fit for Android or iOS users who need a small free allowance and multimodal verification options.

ContentDetector.org suits readers who want a completely free detector with mobile and desktop coverage, though its converter accepts up to 1,000 characters.

GPTZero is worth choosing for its free trial and 10,000-word monthly free tier across web, extension, and API.

It's AI fits users seeking file uploads, deep scans, and an included Chrome extension on its free plan.

Originality.ai is an alternative for users who want document uploads and a pay-as-needed basic tier with three scans per day.

Winston AI is the alternative for readers who also need image detection, OCR scanning, and a time-limited trial.

AI Detector Pro is another web-based freemium option with humanization-focused plans.

Detecting-AI.com suits high-volume, no-account checks with a character-based free allowance and separate humanizer and fact-checker tools.

Verdict

AI Detectors.io is a strong choice for individuals and editorial teams that want detection, revision tools, Word and browser access, and an API in one service. Choose Premium for sustained document work or Developer for sentence-level API automation. Look elsewhere if your priority is LMS integration, non-English benchmark confidence, or minimizing third-party processing of submitted text.