# Turnitin Alternatives 2027: 15 Paid, Free & Open-Source

Source: https://zekaiwork.com/alternatives/turnitin/
Prices checked: 2026-11-13 (Zekai Price Ledger)

The best Turnitin alternatives in 2027 are Copyleaks (best overall, $13.99/mo billed yearly), Quetext (best free plan) and SlopTotal (best open source, MIT). Turnitin: Sold through sales contact; no public price on turnitin.com. Zekai checked these prices on vendor pages on 13 Nov 2026; 12 more are compared below, including 4 with a free plan and 6 open source.

| Tool | Type | Starting price | Free plan limit | Licence | Best for | Price checked | Links |
|---|---|---|---|---|---|---|---|
| Turnitin (the tool being replaced) | — | Sold through sales contact; no public price on turnitin.com. | No | — | — | 2026-11-13 | [pricing](https://www.turnitin.com/products/feedback-studio) |
| Copyleaks | Paid | $13.99/mo billed yearly | No free plan | — | Plagiarism and AI checks for individuals and schools | 2026-11-11 | [site](https://copyleaks.com) [pricing](https://copyleaks.com/pricing) [Zekai page](https://zekaiwork.com/ai-tools/copyleaks/) |
| GPTZero | Paid | Not checked | No free plan | — | Sentence-level AI highlighting for teachers | 2026-11-11 | [site](https://gptzero.me) [pricing](https://gptzero.me/pricing) [Zekai page](https://zekaiwork.com/ai-tools/gptzero/) |
| Originality.ai | Free plan + paid | $12.95/mo billed yearly | 10K words (100 credits), one-time | — | Publishers checking AI text and plagiarism | 2026-11-11 | [site](https://originality.ai) [pricing](https://originality.ai/pricing) [Zekai page](https://zekaiwork.com/ai-tools/originality-ai/) |
| Winston AI | Free plan + paid | $10/mo billed yearly | 2,000 credits over a 14-day trial | — | AI detection with certification for websites | 2026-11-11 | [site](https://gowinston.ai) [pricing](https://gowinston.ai/pricing/) [Zekai page](https://zekaiwork.com/ai-tools/winston-ai/) |
| Quetext | Free plan + paid | $14.99/mo | 1,000 words each for plagiarism and AI checks | — | Students checking essays before submission | 2026-11-11 | [site](https://www.quetext.com) [pricing](https://www.quetext.com/pricing) [Zekai page](https://zekaiwork.com/ai-tools/quetext/) |
| Scribbr | Free | Free plan; paid price not published | Unlimited free AI checks (word cap not stated) | — | Students checking essays before submission | 2026-11-11 | [site](https://www.scribbr.com) [pricing](https://www.scribbr.com/ai-detector/) [Zekai page](https://zekaiwork.com/ai-tools/scribbr/) |
| PlagiarismCheck.org | Paid | Not checked | No free plan | — | Schools wanting quote-based plagiarism checks | 2026-11-11 | [site](https://plagiarismcheck.org) [pricing](https://plagiarismcheck.org/pricing/) [Zekai page](https://zekaiwork.com/ai-tools/plagiarismcheckorg/) |
| Compilatio | Free | Free plan; paid price not published | First student analysis free, top 3 sources shown | — | European schools and universities | 2026-11-11 | [site](https://compilatio.net) [pricing](https://compilatio.net) [Zekai page](https://zekaiwork.com/ai-tools/compilatio/) |
| SlopTotal | Open source | Free (self-hosted) | No limit (self-hosted) | MIT | Self-hosted multi-engine AI text detector | 2026-11-13 | [site](https://sloptotal.com) [code](https://github.com/pablocaeg/sloptotal) [Zekai page](https://zekaiwork.com/free-open-source/sloptotal/) |
| Binoculars | Open source | Free (self-hosted) | No limit (self-hosted) | BSD-3-Clause | Research-grade zero-shot AI text detection | 2026-11-13 | [site](https://github.com/ahans30/Binoculars) [code](https://github.com/ahans30/Binoculars) [Zekai page](https://zekaiwork.com/free-open-source/binoculars/) |
| Dolos | Open source | Free (self-hosted) | No limit (self-hosted) | MIT | Source-code plagiarism checks in programming courses | 2026-11-13 | [site](https://dolos.ugent.be) [code](https://github.com/dodona-edu/dolos) [Zekai page](https://zekaiwork.com/free-open-source/dolos/) |
| Fast-DetectGPT | Open source | Free (self-hosted) | No limit (self-hosted) | MIT | Zero-shot detection from an ICLR 2024 paper | 2026-11-13 | [site](https://fastdetect.net/) [code](https://github.com/baoguangsheng/fast-detect-gpt) [Zekai page](https://zekaiwork.com/free-open-source/fast-detect-gpt/) |
| Open Detector | Open source | Free (self-hosted) | No limit (self-hosted) | MIT | Academic-paper AI detection with a small model | 2026-11-13 | [site](https://github.com/Imalwayshere/Open-Detector) [code](https://github.com/Imalwayshere/Open-Detector) [Zekai page](https://zekaiwork.com/free-open-source/open-detector/) |
| SynthID Text | Open source | Free (self-hosted) | No limit (self-hosted) | Apache-2.0 | Watermark detection for text you generate | 2026-11-13 | [site](https://github.com/google-deepmind/synthid-text) [code](https://github.com/google-deepmind/synthid-text) [Zekai page](https://zekaiwork.com/free-open-source/synthid-text/) |
| JPlag | Open source | Free (self-hosted) | No limit (self-hosted) | GPL-3.0 | Source-code plagiarism checks across many languages | 2026-11-13 | [site](https://github.com/jplag/JPlag) [code](https://github.com/jplag/JPlag) [Zekai page](https://zekaiwork.com/free-open-source/jplag/) |

## How each alternative compares with Turnitin

- **Copyleaks** (Paid, $13.99/mo billed yearly, checked 2026-11-11): Publishes self-serve prices by credit: Personal gives 100 credits a month (up to 25,000 words) and Pro $99.99 monthly for 1,000 credits; Education and Enterprise are by quote. Switch if you want to buy plagiarism and AI checks yourself by monthly credits instead of negotiating an institutional contract. Stay with Turnitin if your institution already runs submissions through its LMS and needs the Similarity Report workflow educators know.
- **GPTZero** (Paid, Not checked): Highlights flagged sentences and lists the models it checks for; Writing Replay plays back how a document was typed, including paste activity, and a free Chrome extension covers Google Docs. Switch if you want to see how a document was written through playback, not just a similarity score. Stay with Turnitin if you need a long-established similarity report against a large submission database and institutional LMS contracts.
- **Originality.ai** (Free plan + paid, $12.95/mo billed yearly, checked 2026-11-11): Charges one credit per 100 words, so an AI plus plagiarism scan uses two; Pro includes 200K words a month and 30-day scan history, with the API on Enterprise. Switch if you check web content for publication and prefer a transparent credit price per 100 words. Stay with Turnitin if you grade student work inside an LMS and need rubric and feedback tools alongside the check.
- **Winston AI** (Free plan + paid, $10/mo billed yearly, checked 2026-11-11): Essential gives 100,000 credits a month and up to 200,000 characters per scan; its free tier is a 14-day trial, and a HUMN-1 certification is offered for website content. Switch if you need a low-cost monthly plan with high per-scan character limits and website content certification. Stay with Turnitin if your school requires an institutional product integrated with its LMS and assignment workflow.
- **Quetext** (Free plan + paid, $14.99/mo, checked 2026-11-11): Essential bundles plagiarism and AI detection at 100K words a month each with an AI humanizer and AITutorMe; Professional at $29.98 doubles to 200K words and 100 bulk-upload files. Switch if you are a student or writer who wants a self-serve pre-submission check with a small free allowance. Stay with Turnitin if your institution needs checks tied to LMS submissions and educator review of reports.
- **Scribbr** (Free, Free plan; paid price not published): The AI detector page advertises unlimited free AI checks plus a Premium AI Detector tier with GPT-4 detection; Scribbr is built for students, not for institution-wide deployment. Switch if you are a student who only needs a free AI check before handing in an essay. Stay with Turnitin if you are an educator who needs submission management, classes and similarity reports.
- **PlagiarismCheck.org** (Paid, Not checked): Education plans are sold by quote only; Advanced supports an English, German, French, Portuguese or Spanish interface while Pro supports any language, and there is no public price list. Switch if you want a smaller education vendor with a quote-based plan and a multilingual interface. Stay with Turnitin if your institution already holds a Turnitin contract and LMS integration it does not want to migrate.
- **Compilatio** (Free, Free plan; paid price not published): Magister serves teachers and Studium lets students self-check; analysis covers more than 40 languages, and plagiarism and AI results appear in one report. Switch if your school works in several languages, especially French, and wants plagiarism and AI results in one report. Stay with Turnitin if you want English-language AI writing detection from a vendor your LMS already integrates with.
- **SlopTotal** (Open source, Free (self-hosted)): Runs 23 detection engines, including Binoculars and Fast-DetectGPT, on your own CPU and returns one calibrated score with per-engine votes, file and URL scanning, and a JSON API. Switch if you want many detectors in one run and published accuracy data you can inspect. Stay with Turnitin if you want a hosted service with no Docker or server to look after.
- **Binoculars** (Open source, Free (self-hosted)): A zero-shot AI-text detector from an ICML 2024 paper that needs no training data; it only scores AI likelihood and does no plagiarism matching, and the repo says academic use with human supervision. Switch if you want to self-host an inspectable AI-text detector for research or your own tooling. Stay with Turnitin if you need plagiarism matching against a source database plus reports and LMS integration.
- **Dolos** (Open source, Free (self-hosted)): Detects source code plagiarism between submissions with similarity scores and a side-by-side compare view, but it checks code only and does not detect AI-written prose. Switch if you teach programming and need to compare student code submissions against each other. Stay with Turnitin if you grade essays and need prose similarity checks against web and publication sources.
- **Fast-DetectGPT** (Open source, Free (self-hosted)): ICLR 2024 zero-shot method using conditional probability curvature; the README reports 0.9887 AUROC on five-model generations and ships a local script, with no dashboard or upload. Switch if you plan to study or extend a zero-shot detector rather than only read scores. Stay with Turnitin if you need reports, accounts or an API with support behind it.
- **Open Detector** (Open source, Free (self-hosted)): BERT-base classifier trained for academic papers; the README claims 99.57% accuracy on its own dataset and says it is stylometric only. It is a model and script, not a web app. Switch if you want a lightweight detector for research-style prose that stays offline. Stay with Turnitin if you need team accounts and support, not a model file.
- **SynthID Text** (Open source, Free (self-hosted)): Google DeepMind reference code that detects only text carrying its SynthID watermark; the frequentist detector gives a binomial p-value for a key, so it cannot flag unwatermarked ChatGPT or Claude output. Switch if you want a statistical test tied to a key, not a style classifier. Stay with Turnitin if you need a score for text written by tools you do not control.
- **JPlag** (Open source, Free (self-hosted)): Finds pairwise similarities among a set of programs and shows them in a report viewer; it compares source code in many languages and does not read essays or detect AI-written prose. Switch if you need software plagiarism and collusion checks across many programming languages, processed locally. Stay with Turnitin if you want similarity matching and AI writing checks in one hosted report for written work.

## Open-source options in detail

- **SlopTotal** (https://github.com/pablocaeg/sloptotal): Licence: MIT; Commercial use: Yes (MIT).; Runs on: Runs on CPU; loaded models need about 8.3 GB of RAM; GPU optional.; Setup: moderate: One docker run command; models download on first start.; Last commit: 2026-11-03; Last release: 2026-11-03; GitHub stars: 114 (2026-11-13)
- **Binoculars** (https://github.com/ahans30/Binoculars): Licence: BSD-3-Clause; Commercial use: Yes for the code (BSD-3-Clause); check the licence of the Falcon models you download.; Runs on: Python 3.9; two 7B models, so a GPU or large-memory machine.; Setup: hard: Clone the repo, pip install, then download two 7B models.; Last commit: 2024-05-14; GitHub stars: 435 (2026-11-13)
- **Dolos** (https://github.com/dodona-edu/dolos): Licence: MIT; Commercial use: Yes (MIT).; Runs on: Node.js 22 or newer, or Docker; a free hosted web app also exists.; Setup: easy: npm install -g @dodona/dolos gives a CLI; web hosting needs Docker.; Last commit: 2026-11-12; Last release: 2026-10-19; GitHub stars: 357 (2026-11-13)
- **Fast-DetectGPT** (https://github.com/baoguangsheng/fast-detect-gpt): Licence: MIT; Commercial use: Yes (MIT).; Runs on: Authors ran it on an 80 GB A100; the local demo defaults to gpt-neo-2.7B.; Setup: hard: Python 3.8 and PyTorch 1.10 environment plus model downloads.; Last commit: 2026-02-07; GitHub stars: 440 (2026-11-13)
- **Open Detector** (https://github.com/Imalwayshere/Open-Detector): Licence: MIT; Commercial use: Yes (MIT); the Hugging Face model card also states MIT.; Runs on: Python with PyTorch and Transformers; BERT-base model, 512-token input.; Setup: moderate: pip install transformers torch, then a short Python script.; Last commit: 2026-11-12; GitHub stars: 254 (2026-11-13)
- **SynthID Text** (https://github.com/google-deepmind/synthid-text): Licence: Apache-2.0; Commercial use: Yes (Apache-2.0), but the repo calls itself a reference implementation, not for production.; Runs on: Any GPU such as a T4 for Gemma 3 270M; GPT-2 runs on CPU.; Setup: moderate: Python virtual environment and a Jupyter notebook from the repo.; Last commit: 2026-10-26; GitHub stars: 1,300 (2026-11-13)
- **JPlag** (https://github.com/jplag/JPlag): Licence: GPL-3.0; Commercial use: Yes; GPL-3.0 means sharing source if you distribute changes.; Runs on: Java SE 25; runs locally, and no code or results are uploaded.; Setup: moderate: Download a release jar and run it on Java 25.; Last commit: 2026-10-05; Last release: 2025-12-11; GitHub stars: 2,000 (2026-11-13)

## Questions

### What is the best alternative to Turnitin in 2027?
Copyleaks is the best overall Turnitin alternative on this page ($13.99/mo billed yearly). For no cost, Quetext has a free plan (1,000 words each for plagiarism and AI checks). To self-host, SlopTotal is open source (MIT).

### Is there a free version of Turnitin?
No. Turnitin has no free plan; paid plans start at Sold through sales contact; no public price on turnitin.com., checked on 13 Nov 2026.

### Is there a 100% free alternative to Turnitin?
Yes. SlopTotal, Binoculars, Dolos, Fast-DetectGPT, Open Detector, SynthID Text, JPlag are open source and free to self-host. Originality.ai, Winston AI, Quetext, Scribbr, Compilatio have a free plan with limits, shown in the table.

### How much do Turnitin alternatives cost for a team of 5?
If each of 5 people buys the entry paid plan, at the prices Zekai checked on 13 Nov 2026, the monthly cost is Winston AI $50/mo, Originality.ai $64.75/mo, Copyleaks $69.95/mo. Team and business plans can cost more per seat. The Zekai Cost Finder on this page recalculates for any team size.

### Which is better, Copyleaks or Turnitin?
Publishes self-serve prices by credit: Personal gives 100 credits a month (up to 25,000 words) and Pro $99.99 monthly for 1,000 credits; Education and Enterprise are by quote. Choose Copyleaks if you want to buy plagiarism and AI checks yourself by monthly credits instead of negotiating an institutional contract. Stay with Turnitin if your institution already runs submissions through its LMS and needs the Similarity Report workflow educators know.

### Why are people leaving Turnitin?
The documented reasons are: Turnitin lists no public pricing: the Feedback Studio page sends buyers to 'Speak to an expert', 'Schedule a call' or 'Contact Sales' (11 Nov 2026); Turnitin's AI writing detection is sold as the Originality add-on and, per its product page, is English only (11 Nov 2026). Each is sourced in the section above.

### Turnitin vs GPTZero: what is the difference?
Turnitin pairs a Similarity Report with an AI writing add-on sold to institutions. GPTZero focuses on AI detection with sentence highlighting and Writing Replay, and also has plagiarism checking.

## Related on Zekai

- [Copyleaks alternatives](https://zekaiwork.com/alternatives/copyleaks/)
- [GPTZero alternatives](https://zekaiwork.com/alternatives/gptzero/)
- [Winston AI alternatives](https://zekaiwork.com/alternatives/winston-ai/)
- [ZeroGPT alternatives](https://zekaiwork.com/alternatives/zerogpt/)
- [AI for Education & E-learning](https://zekaiwork.com/professions/ai-education-elearning-teaching-tools/)

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