Product Information
What is Harper?
Harper is an English grammar checker designed just right. Created after years of dealing with competitors' flaws. Grammarly is too expensive and overbearing—its suggestions lack context and are often flat-out wrong. Plus, it’s a privacy nightmare. Everything you write with Grammarly is sent to their servers. Their privacy policy claims they don’t sell data, but that doesn’t mean they don’t use it to train large language models or worse. The round-trip network requests also make editing tedious. LanguageTool is great if you have GBs of free RAM and are willing to download ~16GB n-gram datasets. Beyond memory demands, I found LanguageTool too slow—even medium-sized documents take seconds to check. That’s why I created Harper: a grammar checker tailored to my needs. It checks documents in milliseconds, uses less than 1/50th of LanguageTool’s memory footprint, and is entirely private. Harper is even small enough to load via WebAssembly.
How to use Harper?
Harper is an English grammar-checking tool designed to provide fast, private, and efficient grammar-checking services, addressing the issues of cost, privacy invasion, and performance in existing tools.
Core Functions of Harper
Privacy focused
Lightweight
No registration required
No Tracking
Ad-free
Usage Scenarios of Harper
- Check grammar errors in English documents
- Quickly proofread text to improve work efficiency
- Handle documents containing sensitive information to ensure privacy and security
- Perform grammar checks on devices with limited memory resources
Common Questions about Harper
What does Harper do?
How do I use Harper?
What are the core features of Harper?
What are the use cases for Harper?
