ForthWrite
ForthWrite drafts replies using a writing profile learned from a user's sent email.
What ForthWrite is
ForthWrite drafts replies using a writing profile learned from a user's sent email. Its free plan works with Gmail and Outlook on the web and allows 10 drafts per week; an Outlook add-in is available for Outlook desktop on Windows or Mac. The free plan excludes custom persona, auto-draft, batch drafting, coaching, analytics, and dictation. Pro is listed at $24 a month billed annually, with the page also showing $29/mo, and adds unlimited drafts, auto-draft, batch drafting, custom persona, RAG, and dictation. Teams has a two-seat minimum and includes Pro features, shared team persona, Prompt Lab, review records, and team analytics. Slack drafting requires Standard or Pro. A Claude connector can create a draft or contact summary but does not send mail or open a mailbox. ForthWrite says it passed Google's CASA Tier 2 assessment for its restricted Gmail read-only scope. Its privacy policy says routine thread content is not retained after a draft is returned, while sent-email snippets are stored to learn the user's voice. It does not currently read or analyze attachments.
Good
- Learns a writing profile from sent email.
- Free plan supports Gmail and Outlook on the web.
- Outlook desktop add-in is available for Windows and Mac.
- Claude connector can draft or provide a contact summary.
Watch out
- Free plan is limited to 10 drafts per week.
- Slack drafting requires Standard or Pro.
- Does not currently read or analyze email attachments.
- Team owners and admins can view and export review records.
Who it suits
ForthWrite suits professional services firms and individuals who write client email in Gmail or Outlook. Teams considering it should account for the review records visible to owners and admins and the storage of sent-email snippets.
Verdict
ForthWrite focuses on drafting email in a user's established writing style, with different features across its plans. Check the draft limits, attachment limitation, and team review access before choosing it.
Plans and prices
From ForthWrite's own pricing page, checked 15 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free | Free | 10 drafts/week · Gmail and Outlook web · voice matching · no API key or card |
| Pro | $24 a month | Unlimited drafts · auto-draft · batch drafting · Prompt Lab · analytics · custom persona · RAG · dictation · monthly |
| Pro annual | $29 a month | Unlimited drafts · auto-draft · batch drafting · Prompt Lab · analytics · custom persona · RAG · dictation · annual; $288/year shown |
| Teams | $59 a month | 2-seat minimum · shared persona · shared Prompt Lab · team analytics · admin invites · 30-day trial · per seat; annual option shown as $79/seat/month |
| Enterprise | Priced on request | 10+ seats · dedicated account management · volume licensing · optional SSO/SAML, SCIM, audit logging and custom DPA |
The facts
Each one read from ForthWrite's own pages, with the date it was checked.
What it does
- AI providers
- The Outlook page lists BYOK support for OpenAI, Anthropic, Google, xAI, DeepSeek, Mistral, Perplexity, Cohere, and Groq.checked 30 Sep 2026
- Analytics
- The dashboard reports acceptance, similarity, edit distance and estimated time saved.checked 15 Oct 2026
- Attachment limit
- ForthWrite currently does not analyze PDF, document or spreadsheet attachments in email threads.checked 15 Oct 2026
- Auto-draft
- Paid plans can prepare replies automatically as new email arrives.checked 15 Oct 2026
- Batch drafting
- Paid plans can process many email threads in parallel.checked 15 Oct 2026
- Calendar support
- The extension can read free/busy information and create a calendar invitation only after the user confirms it.checked 15 Oct 2026
- Chrome listing
- The Chrome listing shows 56 users, version 7.3.13, a 577 KiB package and an August 20, 2026 update.checked 15 Oct 2026
- Claude connector
- The hosted MCP connector exposes draft and read-only contact-context tools and does not send mail or open a mailbox.checked 15 Oct 2026
- Data handling
- The privacy policy says routine thread content is not retained after a draft is returned, while sent-email snippets are stored to learn the user's voice.checked 30 Sep 2026
- Data isolation
- Sent-email snippets are account-scoped and are not used to train shared or generalized models.checked 15 Oct 2026
- Email clients
- The free plan works in Gmail and Outlook on the web, and the Outlook add-in is available for Outlook desktop on Windows or Mac.checked 30 Sep 2026
- Founder and location
- About information identifies Curtis Boortz as the founder and places the operation in San Diego, California.checked 15 Oct 2026
- Gmail and Outlook
- The Chrome extension works in Gmail and Outlook Web, and the same voice profile can span both.checked 15 Oct 2026
- Independent praise: onboarding
- Uneed's hands-on test said onboarding inferred tone, forbidden phrases and sign-offs from the sent folder.checked 15 Oct 2026
- Intent awareness
- ForthWrite treats introductions, follow-ups and status updates as different drafting intents.checked 15 Oct 2026
- Launch milestone
- An Indie Hackers post dated June 22, 2026 described ForthWrite as two weeks post-launch after about a year of building, with a few dozen trial users and no monthly revenue at that point.checked 15 Oct 2026
- Licence
- The terms state that ForthWrite software, branding and proprietary systems remain the company's property and prohibit reverse engineering.checked 15 Oct 2026
- Limit: detector error
- Uneed found the forbidden-phrase detector could flag phrases that were not actually present.checked 15 Oct 2026
- Limit: language mismatch
- Uneed reported that a French inbound thread produced an English draft despite the matching setting.checked 15 Oct 2026
- Limit: session friction
- An IndieAppCircle tester complained about repeated logins and multiple permission screens after returning to the extension.checked 15 Oct 2026
- Limit: sparse training
- Uneed measured 56% voice matching on a sparse 22-sample benchmark and said more captured emails were needed for stronger calibration.checked 15 Oct 2026
The company
- Company
- ForthWrite is operated by Aesir Labs, LLC; its founder is Curtis Boortz, listed in San Diego, California.checked 30 Sep 2026
- Company size
- Crunchbase lists ForthWrite as an active private software company with 1–10 employees and Curtis Boortz as founder.checked 15 Oct 2026
- Maker
- Aesir Labs, LLC operates the product under the ForthWrite name.checked 15 Oct 2026
Getting started
- Open the ForthWrite website.
- Choose the Free, Pro or Teams plan; Free has 10 drafts per week and Teams requires at least two seats.
- Use the free plan with Gmail or Outlook on the web, or use the Outlook add-in with Outlook desktop on Windows or Mac.
- For Slack drafting, use the available message or compose shortcuts, or the /forthwrite command, on Standard or Pro.
Limits worth knowing
The Free plan allows 10 drafts per week and excludes custom persona, auto-draft, batch drafting, coaching, analytics and dictation. Teams requires a two-seat minimum and has a 30-day trial.
Questions
Is there a free plan?
Yes. Free costs nothing and allows 10 drafts per week for Gmail and Outlook on the web.
How much does Pro cost?
Pro is listed at $24 a month, billed annually; the page also shows $29/mo.
What does Teams cost?
Teams is listed at $59 a month. The page also shows $79/seat/mo with a 25% saving, and the plan requires at least two seats.
Which email clients does it support?
The free plan works with Gmail and Outlook on the web. An Outlook add-in is available for Outlook desktop on Windows or Mac.
Does it work with Slack or Claude?
Slack drafting requires Standard or Pro. The Claude connector can generate a draft or contact summary, but it does not send email or open a mailbox.
Does ForthWrite analyze attachments?
No. ForthWrite says it does not currently read or analyze email attachments.
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