IsItAI vs Copyleaks: AI detector comparison
A side by side look at pricing, methodology, language support and best-fit use case. Every claim on this page is linked to a source at the bottom.
Last updated . Reviewed by IsItAI Editorial.
At a glance
IsItAI
UK, 2024UK-built AI detection that gives you a confidence score, not a verdict.
- Pricing
- From £4.99/month
- Free tier
- 5 scans/day free
- API
- Yes
- Languages
- 30
Copyleaks
Israel, 2015Enterprise-grade detection with multilingual support.
- Pricing
- From $9.99/month (100 credits)
- Free tier
- Limited free credits
- API
- Yes
- Languages
- 30
Side by side
| Feature | IsItAI | Copyleaks |
|---|---|---|
| Free tier | 5 scans/day free | Limited free credits |
| Starting price | From £4.99/month | From $9.99/month (100 credits) |
| Cost per 1k words | £0.05 (Pro plan equivalent) | $0.10 |
| API available | Yes | Yes |
| Languages supported | 30 | 30 |
| Founded | 2024 | 2015 |
| Country | UK | Israel |
| Primary audience | Educators, recruiters and content teams | Enterprises and institutions |
| Best for | Teachers, students and recruiters who want a clear confidence score and source-passage highlighting | Enterprise teams needing multilingual detection and integrations |
| Known weakness | Smaller brand than US incumbents | Pricier than competitors for low-volume users |
How each tool works
IsItAI
Method: Multi-model ensemble. Combines several open detectors and weights agreement. Returns a confidence band rather than a binary verdict.
Data handling: GDPR compliant. UK and EU hosted. Submitted text is not stored after the scan completes.
Copyleaks
Method: Proprietary classifier with paraphrasing-resistance claims. Integrates with LMS and CMS platforms.
Data handling: Enterprise tier offers no-storage option. Default plan stores submissions.
How accurate are AI detectors? What the research says
Two findings from independent academic research apply to almost every detector on this list, including IsItAI and Copyleaks.
1. False positives on non-native English writers. Liang et al. (Stanford, 2023) found that GPT detectors flagged over half of TOEFL essays written by non-native English speakers as AI-generated, while flagging almost none of the essays from US students. If your use case involves non-native English writers, never treat a detector verdict as proof on its own.
2. Paraphrasing reliably defeats classifiers. Sadasivan et al. (Maryland, 2023) showed that running AI output through a paraphraser drops detection performance close to chance. Both IsItAI and Copyleaks are vulnerable to this.
Where IsItAI wins
- Lower entry price at £4.99/month versus $9.99 for 100 Copyleaks credits, and a more generous free daily allowance.
- Built specifically for AI detection rather than as one feature inside a plagiarism suite.
- GDPR compliant UK and EU hosting. Copyleaks' default plan stores submissions outside the EU.
Where Copyleaks wins
- Multilingual coverage at 30 languages with documented paraphrasing-resistance claims.
- Native integrations with major LMS and CMS platforms suit enterprise procurement.
- Enterprise tier offers a verified no-storage option for sensitive content.
Which one should you pick, IsItAI or Copyleaks?
Pick IsItAI for UK and EU teams who want focused AI detection with predictable pricing. Pick Copyleaks if you are an enterprise needing multilingual scale and LMS integrations and you can negotiate the no-storage tier. Both are vulnerable to paraphrasing attacks (Sadasivan et al. 2023).
Frequently asked questions
Is IsItAI free?
5 scans/day free
Is Copyleaks free?
Limited free credits
Can either tool be fooled by paraphrasing?
Yes. Sadasivan et al. (2023) demonstrated that paraphrasing reliably defeats most AI classifiers. Treat any detector verdict as a screening signal, not proof.
Are AI detectors fair to non-native English writers?
Independent research (Liang et al. 2023) found high false-positive rates for non-native English writing. Always combine a detector signal with other evidence, never use it as a sole basis for an academic or hiring decision.
Which one should I pick if I have to choose one, IsItAI or Copyleaks?
Pick IsItAI for UK and EU teams who want focused AI detection with predictable pricing. Pick Copyleaks if you are an enterprise needing multilingual scale and LMS integrations and you can negotiate the no-storage tier. Both are vulnerable to paraphrasing attacks (Sadasivan et al. 2023).
Try IsItAI free
5 free scans a day. No credit card. UK hosted and GDPR compliant.
Sources and further reading
- IsItAI homepage
- Pricing
- How it works
- Copyleaks AI content detector
- Copyleaks pricing
- Liang et al. (Stanford, 2023): GPT detectors are biased against non-native English writers
- Sadasivan et al. (2023): Can AI-generated text be reliably detected?