Chrome Extensions for Writing

Writing Chrome extensions inject themselves into any text field on the web — email composers, Slack inputs, Notion editors, social media composers, CMS publishing flows, customer support tools. That ubiquity is what makes them valuable, and what makes the subscription model on them feel especially exploitative when the underlying technology (an OpenAI or Anthropic API call) is the same across products.

The category splits into a few clear shapes: AI drafters that generate prose from a prompt, paraphrasers that rewrite selected text in a different tone or length, grammar and clarity tools that suggest edits on text you've already written, and content helpers that handle specific writing workflows (LinkedIn posts, sales emails, customer support replies, blog drafts).

The advantage of building your own: every paid writing extension has a "voice" — a default tone, a default verbosity, default vocabulary it's been tuned to. None of them sound exactly like you. A custom extension can be tuned to your specific writing samples, your industry's tone, and your team's terminology. It's not just cheaper than paid alternatives — it produces better output for your specific case.

Writing extensions you can build

Chrome Extension That Drafts LinkedIn Posts with AI

Right-click any text on the web, get an AI-drafted LinkedIn post version of it.

beginner

Chrome Extension That Counts Words on Any Selection

Highlight any text, see word count, character count, and estimated reading time instantly.

beginner

More writing extensions coming soon.

Writing alternatives

WriteSeed alternative

WriteSeed alternative — build your own AI writing extension with PlugThis for $89 lifetime. Full source code, no subscription, in 5 minutes.

Wordtune alternative

Wordtune alternative — build your own AI rewriting Chrome extension with PlugThis. $89 lifetime, no subscription, your own API keys.

QuillAI alternative

QuillAI alternative — build your own AI writing Chrome extension with PlugThis. $89 lifetime, your own AI keys, full source code.

Why build your own writing extension

•Tune the AI on your own writing samples — output sounds like you, not like a generic assistant
•Skip $10–30/month writing tool subscriptions
•Build per-context modes — one tone for emails, another for LinkedIn posts, another for documentation
•Combine writing tools with internal references (saved snippets, your style guide, approved language)
•Privacy — your drafts hit the AI API directly, not via a SaaS that may train on your text

Popular subcategories

AI drafters

Long-form writers, email drafters, social post generators

Paraphrasers & rewriters

Tone changers, length adjusters, formality switchers

Grammar & clarity

Editors, simplifiers, style enforcers

Writing workflows

LinkedIn helpers, customer support templates, sales email composers

Frequently asked questions

How is a custom AI writer different from Grammarly or Wordtune?

Grammarly and Wordtune use the same foundational AI tech available to everyone (OpenAI, Anthropic, their own models). Their value is the UX wrapper plus the brand. A custom build replicates the UX, lets you tune the AI to your writing, and replaces the monthly fee with API usage that's typically 10–20× cheaper.

Can I train a Chrome extension on my own writing?

Yes, two ways. Simple: include 5–10 of your writing samples in the system prompt — the model will mimic style on every output. Advanced: fine-tune a custom model on your full corpus and point the extension at it.

Will my custom writing extension work in Gmail and Notion?

Yes. Both Gmail and Notion use standard contenteditable fields that extensions can detect and inject into. PlugThis handles this — describe the platforms you want it to work in, and the generated extension will include the right content scripts.

Can I build a writing extension that doesn't use AI?

Yes. Non-AI writing tools include word counters, readability scorers, find-and-replace utilities, snippet expanders, and template inserters. These run entirely client-side — no API costs at all.

Build your own writing extension

Describe what you want in one sentence. PlugThis generates a working Manifest V3 Chrome extension in under two minutes.

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