Coda One

About the tool

Coda One is a browser-based AI writing platform for students, bloggers, freelancers, marketers and content teams who want to check a draft and edit it in one place. It combines four tools: an AI Detector, an AI Humanizer, an AI Rewriter and a Grammar Checker. All four also run from the right-click menu of a Chrome extension that works on most web pages and Chromium browsers, so text can be checked or edited inside email, documents and web apps. The AI Detector marks the sentences that carry AI tells and explains the reason for each flag, using patterns such as stock connectors, hedging filler and overused structures. It runs on Coda One's own servers, reads English only, and the company states that a score is a starting point rather than proof of authorship. The AI Humanizer offers 9 writing modes and the AI Rewriter 8 tones, while paid plans add Brand Voice. These writing tools use OpenAI GPT-4o mini by default, with Google Gemini and DeepSeek as fallbacks, and Coda One says submitted text does not train its models. The free plan needs no card and includes the AI Detector with no daily limit, plus 3 runs a day on each writing tool, or 5 with a free account. Starter costs $9.99 per month for 30,000 words, Pro $19.99 for 100,000 words and Business $39.99 for 500,000 words, with yearly billing about 20% cheaper. Plans are single-user, and a 7-day money-back guarantee applies to the first purchase under set usage conditions.