Compose AI vs HyperWrite

Two fact sheets from our own research, side by side — pricing, platforms, API access and status re-checked by us rather than quoted from the vendors.

The short answer

Free plan: Both have one
Best fit: Compose AI: Heavy email writers who churn out routine replies in Gmail · HyperWrite: People who draft mostly in Gmail or Google Docs and want suggestions in place
Platforms: Compose AI: Chrome extension · HyperWrite: Web, Chrome extension
Trust score: About even — Compose AI 90, HyperWrite 91
Status: Both up at our last check (Sep 6, 2026)

From our own records as of each tool's last check. Anything we have not confirmed is left out rather than guessed. How we verify

Compose AIFree Chrome extension that autocompletes sentences and email replies as you type across the web

HyperWriteWriting assistant with autocomplete in the browser, cited research and saved custom tools

Side by side

Fact	Compose AI	HyperWrite
Category	AI Writing Assistants	AI Writing Assistants
Pricing model	Freemium	Freemium
Starts at	—	$16/mo
Trust score	90 / 100	91 / 100
Platforms	Chrome extension	Web, Chrome extension
Company	Compose AI, Inc.	OthersideAI, Inc.
Launched	2021	—
Last verified	Sep 6, 2026	Sep 6, 2026

What our research says

Compose AI

A low-friction way to speed up routine email and doc writing, since the free tier installs in a minute and completes sentences anywhere in Chrome. The catch is stagnation risk: the site's own copyright is frozen at 2024 and browser-native AI features increasingly do the same job for nothing.

Pros

Basic extension is free with no time limit
Autocomplete works across most web text fields, not one app
Learns personal writing style for suggestions

Cons

Chrome-only, with no API or desktop apps
Official pricing was unreadable in this check, an odd sign for a paid product
Site freshness signals suggest limited ongoing development

HyperWrite

HyperWrite's useful part is the extension: autocomplete that follows you into Gmail and Google Docs, and a shelf of saved prompt tools you can trigger without opening a chat window. The web app is a competent but ordinary chat-plus-tools workspace in a market where Claude, ChatGPT and Gemini all now write and cite, so the question is whether the 250-message Premium quota and the in-browser convenience are worth $16 to $20 a month to you. The agent that once headlined the product survives only as an 'early access' line on the Ultra plan.

Pros

Chrome extension brings autocomplete and tools into Gmail, Google Docs and most text fields
Research mode returns citations from web and scholarly sources rather than unsourced prose
Custom tools and personas let you package a repeatable prompt once and reuse it
Annual billing cuts Premium to $16 a month, with a free tier to try first

Cons

250 AI messages a month on Premium is low for anyone using it as a daily chat assistant
The free plan's limits are not stated beyond 'limited monthly credits'
The browsing agent is no longer a shipped feature, only early access on Ultra
No legal entity, address or country on the site beyond the OthersideAI brand name

Which one fits

Choose Compose AI if you need

Heavy email writers who churn out routine replies in Gmail
Non-native English speakers who want inline phrasing help
Anyone testing writing autocomplete without paying

Choose HyperWrite if you need

People who draft mostly in Gmail or Google Docs and want suggestions in place
Students and researchers who want cited sources attached to drafts
Anyone who repeats the same prompt jobs and wants them saved as one-click tools