Wordtune

Overview

Wordtune is an AI writing assistant from AI21 Labs aimed at students, professionals, and non-native English writers who want to rewrite, polish, and check text they already have. It is best known for its context-aware rewrite and paraphrase suggestions, and it bundles tone control, summarization, grammar checking, AI generation, a humanizer, and translation. It launched in October 2020 as AI21's first consumer product and reportedly reached around 10 million users (mostly free) at its peak. AI21 Labs was founded in 2017 in Tel Aviv by Yoav Shoham, Ori Goshen, and Amnon Shashua.

Note on status: multiple reports (April 2025) say AI21 halted active development of Wordtune to refocus on enterprise language models. The product is still live and sold on free and paid tiers as of this review, so it is marked generally available, but buyers should weigh the uncertain roadmap.

What it does

The core feature is inline rewriting: select a sentence and Wordtune offers several context-based paraphrases to make it clearer or more authentic, and you accept one. Around it sit tone shifting (formal/casual), sentence shorten/lengthen, synonyms, and 'Spices' (prompts like expand-on, give an example, or add a counterargument). It also flags grammar, spelling, and punctuation issues, summarizes articles, documents, webpages, and YouTube videos, generates original copy from context, humanizes AI-written text, and does AI-assisted translation into English from 10 languages. Across all of these the user reviews and applies each suggestion, so Wordtune is a copilot/assistant, not an autonomous agent: it does not research, plan, or take actions on its own.

Integrations & setup

Wordtune runs as a web app and ships browser extensions for Chrome, Edge, Safari, and Firefox, plus an iOS app. The extension works inside common surfaces such as Gmail, Google Docs, Microsoft Word, Outlook, Microsoft 365, Slack, LinkedIn, X (Twitter), and WhatsApp Web, overlaying suggestions directly where you write. There is no documented public API, MCP server, or agent protocol, so it does not plug into automation or agent workflows.

Pricing

Freemium. The free Basic tier reportedly allows about 10 rewrites and AI suggestions per day, a few AI summaries, and unlimited spelling/grammar checks. Paid plans are Advanced (about $6.99/month month-to-month, around $4.89/month billed annually) with higher daily limits, and Unlimited (about $9.99/month month-to-month, around $6.99/month billed annually) with unlimited rewrites, suggestions, and summaries. A 3-day free trial is offered on paid plans. Regional pricing varies, so confirm on the pricing page.

Best for / not for

Best for students, professionals, and non-native English speakers who want a reliable, affordable tool to rewrite, rephrase, set tone, summarize, and proofread existing text directly inside the browser, Gmail, Docs, and Word. Not for teams that need autonomous content generation, web research, API access, or anything that takes actions on its own, and not ideal for buyers who need a guaranteed long-term roadmap given AI21's reported shift away from the product.

Alternatives

Grammarly and QuillBot are the closest direct competitors on inline rewriting and grammar. For generative, marketing-oriented writing, Jasper, Copy.ai, and Writer compete, though they target content generation more than paraphrasing and proofreading.