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Decision snapshot

Fast-read signals for fit, pricing, and trust.

Category
Content Marketing & Copywriting
Best for
ai writer
Pricing
Freemium
Access
Free plan available

What is this tool?

Lex suits people who revise their own writing, such as newsletter writers, marketers and academics, and want critique and line edits next to the text rather than generated articles. The free plan is usable for light work but is capped at 30 Ask Lex messages a day and a lighter set of models. Before paying, note that Lex's own pages give different Lex Pro prices and different refund windows.

By QT Desk
Read full overview

You write or paste a draft into a Lex document and bring the AI in where you want it: a question in the side chat, a rewrite of a highlighted passage, or a run of Checks that marks suggested edits in place. Prompts you use often and the background knowledge they need can be saved and shared, documents can be edited together live, and a finished piece goes out as a read-only link, an export (Word, PDF, Markdown, HTML or LaTeX) or a Kit draft.

Lex Pro is sold monthly or yearly and renews at the then-current fee until cancelled. Lex's pages disagree on what it costs: the checkout tables embedded on the pricing page and Lex's own 'Lex Pricing Information' document give different monthly and yearly prices. They also disagree on refunds: the pricing FAQ offers a refund if you don't love Lex after a month, while the terms allow a full refund only within ten calendar days of the first purchase and treat it as final after that.

Lex says it does not train AI models on customer writing and would email users with an opt-out before any change; prompts go to OpenAI, Anthropic and Together.ai through enterprise APIs whose providers do not train on that data, and staff do not open documents without written permission. Users keep ownership of what they write, and the terms license it to Lex only to run the service.

Is this right for you?

Quick fit check against how you actually work.

ai writer
Choose this if
  • You write and revise your own drafts and want critique, rewrites and line edits beside the text rather than generated articles
  • You want to pick which AI model reviews your writing, including premium models on Lex Pro
  • You publish through Kit and want drafts and subject lines prompted from your past newsletters, then sent straight to Kit
  • Your use is light enough for the free limits, such as up to 30 Ask Lex messages a day, with no card
Consider alternatives if
  • You want long-form content produced for you; Lex is organised around feedback on writing you do yourself
  • Your team finishes work in Google Docs or relies on track changes: the FAQ rules out direct Google Docs export and track changes is still listed as coming soon
  • You need a settled Lex Pro price before subscribing: the checkout tables and Lex's own pricing document state different prices
  • Refund terms matter: the pricing FAQ offers a refund after a month of use, but the terms limit full refunds to ten days after purchase

Key features

What you can actually do with this tool.

Ask Lex

A side chat that discusses the draft or a highlighted passage: feedback, rewrites, brainstorming.

Checks

AI line edits for brevity, grammar, readability and more, shown as highlights in the text with an explanation you can accept or ignore.

Reusable prompts and Context Tags

Save your own prompts and background knowledge once and share them with a team, so everyone's drafts get the same instructions.

Your choice of AI model

Pick the model inside Lex from OpenAI, Anthropic and TogetherAI-hosted models; premium models are Lex Pro only, and free accounts get a lighter set.

Collaboration and export

Live collaboration by link, comments, version history and read-only publishing links; export to Word, PDF, Markdown, HTML and LaTeX. Track changes is listed as coming soon.

Kit and a small API

A Kit integration studies past newsletters to prompt drafts and subject lines in your voice and sends the finished draft to Kit; a REST API creates, lists and updates documents.

Integrations

Tools and platforms this connects with.

Kit (formerly ConvertKit)REST API

Frequently asked

Common questions about this tool, answered.

Is Lex free?

Yes. Lex can be used free with no card, within limits: 30 Ask Lex messages a day, 5 saved-prompt runs and 30 Checks a month, a small daily AI budget after which AI features pause until the next day, and a lighter set of AI models.

How much does Lex Pro cost?

Lex publishes two different prices. The checkout tables on the pricing page show $24.99 a month or $179.88 a year, with a 7-day free trial on the yearly plan only; Lex's 'Lex Pricing Information' document and its FAQ show $18 a month or $12 a month billed annually ($144 a year). Either way Lex Pro includes $30 of AI credits a month; Lex does not say how far those credits go.

Does Lex train AI on my writing?

No, according to Lex, and it says it would email users with an opt-out before changing that. The model providers it sends prompts to do not train on them either, and you keep ownership of your writing.

What formats can I export to?

Word, PDF, Markdown, HTML and LaTeX, or a read-only publishing link. The FAQ says direct export to Google Docs is not supported.