iLang Detect and Sapling AI Detector take different approaches to catching AI-generated text. iLang is completely free with no signup needed, and it gives you a sentence-by-sentence breakdown of issues across six dimensions, along with fix suggestions. Sapling is a freemium tool that offers token-level classification and perplexity scores, with a free plan limited to 2,000 characters per query and 20 snippets.
So which tool should you use? That depends on whether you want to fix your writing or just get a score. iLang helps you improve your text directly, while Sapling is better for developers who need an API or educators who need to check long documents. But iLang's combination of free access and actionable feedback makes it stand out for writers and editors.
Side by side
scroll sideways on small screens →| Feature | iLang Detect | Sapling AI Detector |
|---|---|---|
| Pricing | Free | Freemium; Pro $25/mo monthly or $12/mo billed annually; usage-based API with a $5 minimum |
| Free tier | Free to use, no signup | Free plan: up to 2,000 characters per AI-detector query, 20 snippets, free domains only |
| Output style | Sentence-level issue list across 6 dimensions (vocabulary, structure, tone, punctuation, logic, rhythm) plus an AI probability score | Overall score plus per-sentence perplexity and token-level classification |
| Languages | English (Chinese version at detect.ilang.cn) | None stated on detector page |
| Fix suggestions | Yes: every flagged fragment gets a problem explanation and a fix suggestion, plus overall rewrite advice | Not advertised; detection only |
| API | Not public yet | Yes |
| Best for | Writers and editors who want to fix the text, not just get a score | Educators, SEO practitioners, content reviewers, hiring/recruiting teams, developers integrating detection |
| Vendor accuracy claim | No accuracy percentage claimed. iLang shows the markers themselves, so you can judge every flag instead of trusting a number. | "97%+ detection rate for AI-generated content" and "less than 3% false positive rate for human-written content" on longer texts; page also states no detector (including Sapling's) should be used as a standalone check. Source: sapling.ai |
Where they differ
Free vs Freemium Model
iLang is completely free with no signup required and no rate limits. You can check as much text as you want. Sapling's free plan is limited to 2,000 characters per query, 20 snippets, and only free domains. To get higher limits, you need to pay $25 per month for Pro or $12 per month billed annually. This makes iLang much more accessible for casual users and students who don't want to pay.
Detection Output: Fixes vs Scores
iLang doesn't just give you a probability score. It analyses your text sentence by sentence across six dimensions: vocabulary, structure, tone, punctuation, logic, and rhythm. Each flagged fragment comes with an explanation and a fix suggestion. Sapling provides an overall score plus per-sentence perplexity and token-level classification, but it doesn't offer any guidance on how to improve the writing.
Accuracy and Third-Party Testing
Sapling claims a 97% detection rate and less than 3% false positive rate on longer texts. However, a March 2026 third-party benchmark of 2,400 samples scored it at 76% overall accuracy with a 17% false positive rate, the highest among six detectors tested. Nearly half of Claude-generated content passed undetected. iLang doesn't make such claims, but its focus on sentence-level issues gives writers a more practical tool.
Which one to pick
Choose Sapling if you need an API for high-volume detection or want to check uploaded PDFs and DOCX files.
Sapling offers a usage-based API with a $5 minimum, making it suitable for developers who need to integrate detection into their workflows. It also supports file uploads of PDF and DOCX documents, and has a browser extension. These features are not available in iLang, which is a web-only tool.
Choose iLang if you want to improve your writing while detecting AI-generated text for free.
iLang is completely free with no signup and no rate limits. It gives you sentence-level explanations and fix suggestions across six dimensions, helping you rewrite problematic sections. Sapling only gives you a score and perplexity data, without any guidance on how to fix the text.
Use both if you want to cross-check results and get the benefits of both detection and fix suggestions.
Run your text through Sapling first to get a token-level probability score, then use iLang to see which sentences need improvement and get specific rewrite suggestions. This way you get the confidence of a second opinion and the practical help of actionable fixes.
Frequently asked questions
Yes, iLang is completely free to use with no signup required. There are no rate limits, no character limits, and no hidden charges. You can check as much text as you want without paying anything.
Yes, Sapling offers a usage-based API for high-volume detection. It has a $5 one-time minimum payment. You can check the documentation at sapling.ai/docs/api/detector for details on how to integrate it.
Sapling claims a 97% detection rate, but a third-party benchmark in March 2026 found it had 76% accuracy with a 17% false positive rate. iLang doesn't make accuracy claims, but its sentence-level analysis helps you understand and fix issues.
Absolutely. You can use Sapling to get a quick probability score and then use iLang to get detailed sentence-level feedback with fix suggestions. This combination gives you both a detection check and a practical editing tool.
See the issues, not just the score
Paste the same draft you ran through Sapling. Free, no signup, nothing stored.