Side by side
iThenticate vs Viper
Both stand on ai plagiarism checkers. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Paid APIWeb
iThenticate focuses on source matching and structured similarity review for manuscripts and other high-stakes documents. Check its paid plans, upload limits, and organizational API requirement against your review process.
Visit iThenticate Free plan Web
Viper offers document checks, configurable scan controls, and downloadable reports through a web app. Consider the free scan limit and one-time credit packages when estimating how much checking you need.
Visit ViperThe facts
| iThenticate | Viper | |
|---|---|---|
| Free plan | No | Yes |
| Open source | Not published | Not published |
| Runs on | API, Web | Web |
| Lowest paid plan | Single: $125, paid once | See the plans |
| Plans published | 3 | 7 |
| Maker | Not published | Not published |
| Website | ithenticate.com | scanmyessay.com |
| On ai plagiarism checkers | #22 of 26 | #18 of 26 |
iThenticate: what it does well
- Compares submissions with billions of listed sources
- Provides multiple Similarity Report views
- Supports Crossref Similarity Check
- Offers PDF export and LMS integration
- Includes organizational API access
What to know first
- No free plan
- Individual packages lack AI writing detection
- API requires an organizational account
- Uploads have file, page, and word limits
Viper: what it does well
- Checks for plagiarism and AI-generated content
- Supports more than 100 languages
- Can scan up to five files at once
- Reports include highlighted matches and source URLs
- Offers downloadable PDF reports
What to know first
- Free service is limited to one scan per document
- Free scan limit is 5,000 words per document
- No free trial is offered
- No longer available as downloadable software
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