Software Alternatives, Accelerators & Startups

Dia VS ForthWrite

Compare Dia VS ForthWrite and see what are their differences

Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

Dia logo Dia

Dia is a GTK+ based diagram creation program for GNU/Linux, MacOS X, Unix, and Windows, and is released under the GPL license.

ForthWrite logo ForthWrite

Email that sounds like you, and gets measurably more like you every week. Drafts in Gmail, Outlook, and the browser. Free to start.
Visit Website
  • Dia Landing page
    Landing page //
    2022-10-12
  • ForthWrite Landing Page
    Landing Page //
    2026-06-19
  • ForthWrite Dashboard
    Dashboard //
    2026-06-19
  • ForthWrite In Gmail
    In Gmail //
    2026-06-19
  • ForthWrite Pricing
    Pricing //
    2026-06-19

ForthWrite is an AI email writing assistant for Gmail and Outlook that learns your writing style from your real sent mail. The more you use it, the more it sounds like you. Get smart drafts in seconds, auto-draft replies before you open your inbox, and maintain your personal voice at scale. Free to start, no credit card required. Works inside Gmail and Outlook on the web.

How it works

ForthWrite captures your tone, sentence rhythm, and sign-offs from your actual sent emails, then uses that profile to generate drafts that match how you write, not a generic AI voice. Every draft you edit or send improves the model over time.

Key features

  • Auto-draft: replies waiting in Gmail before you open your inbox
  • Voice matching from your real sent mail, not templates
  • Recipient-aware drafts that adapt to who you are emailing
  • Prompt Lab for version-controlling and A/B testing your persona prompt
  • BYOK support: bring your own API key for Claude, OpenAI, Grok, Mistral, and more
  • Works in Gmail and Outlook on the web, plus a standalone browser widget
  • Training data export and full data portability

Who uses it

Professionals who send high volumes of relationship-critical email: lawyers, financial advisors, recruiters, account executives, founders, and anyone who wants their inbox handled without sounding like a chatbot wrote it.

Pricing

Free tier includes 10 drafts per week with no credit card required. Paid plans start at $12/month and include unlimited drafts, custom persona prompts, and auto-draft.

Dia

Pricing URL
-
$ Details
-
Platforms
-
Release Date
-
Startup details
Country
Germany

ForthWrite

$ Details
freemium $12.0 / Monthly (Standard plan)
Platforms
Web
Release Date
2026 June
Startup details
Country
United States
State
California
City
San Diego
Founder(s)
Curtis Boortz
Employees
1 - 9

Dia features and specs

  • Open Source
    Dia is free and open-source software, which means you can use it without any cost and even modify the source code to fit your needs.
  • Cross-Platform
    Dia is available for multiple operating systems including Windows, Linux, and macOS, providing flexibility for users on different platforms.
  • Versatile Diagram Types
    Supports a wide range of diagram types such as flowcharts, network diagrams, UML diagrams, and many more, making it a versatile tool for various purposes.
  • Customizable Toolset
    Users can create custom shapes and objects, allowing for detailed and specific diagram creation tailored to unique needs.
  • User Community and Documentation
    There is an active user community and extensive documentation available to help users troubleshoot and get the most out of the software.

Possible disadvantages of Dia

  • Outdated Interface
    The user interface of Dia is somewhat outdated compared to modern diagramming tools, which can make it less intuitive and harder to use.
  • Limited Features
    While versatile, Dia lacks some of the advanced features available in other professional diagramming tools, such as sophisticated collaboration tools and real-time updating.
  • Performance Issues
    Users have reported performance issues, especially when working with very large or complex diagrams, making it less efficient for more intensive tasks.
  • Learning Curve
    Despite its simplicity, there is still a learning curve associated with getting the most out of Dia, particularly for users who are new to diagramming software.
  • Compatibility and Integration
    Dia may not integrate as seamlessly with other modern tools and platforms, potentially creating challenges in workflows that require interoperability with other software.

ForthWrite features and specs

  • Voice Matching
    Learns from your real sent mail, not templates
  • Auto-draft replies
    Replies waiting in Gmail before you open your inbox
  • Batch-drafting
    Draft replies for your entire inbox with one click
  • Works in browser
    Gmail, Outlook, and web browsers
  • BYOK support
    Claude, OpenAI, Grok, Mistral, and more
  • Prompt Lab
    Version control and A/B test your persona prompt
  • Free tier
    10 drafts per week, no credit card required

Analysis of Dia

Overall verdict

  • Dia is a solid choice for users seeking a free and open-source alternative for diagram creation, especially for those who do not require the advanced features found in premium diagramming software.

Why this product is good

  • Dia is often considered a good diagramming tool because it is open-source, platform-independent, and supports a wide range of diagram types including flowcharts, network diagrams, and UML diagrams. It has a user-friendly interface resembling other popular tools like Microsoft Visio, and it offers flexibility with its customizable shapes. Additionally, Dia allows you to export diagrams into various formats such as PNG, SVG, and PDF.

Recommended for

  • Students and educators who need a cost-effective diagramming tool.
  • Individuals and teams working on Linux or open-source environments.
  • Professionals creating various types of basic diagrams without the need for complex features.
  • Users looking for a lightweight application that fulfills typical diagramming requirements.

Analysis of ForthWrite

Overall verdict

  • I don't have verified information about a product called ForthWrite (forthwrite.ai). I cannot confirm its features, quality, or reputation, so I'm unable to provide an accurate assessment of whether it's good.

Why this product is good

  • No reliable data available on this specific product in my knowledge base
  • This may be a newer product, a niche tool, or possibly a fictional/hypothetical name
  • Providing details without verified information could result in inaccurate or fabricated claims

Recommended for

  • Unable to determine without verified product information
  • Consider checking the official website, user reviews on platforms like G2 or Trustpilot, and independent tech review sites for accurate details

Category Popularity

0-100% (relative to Dia and ForthWrite)
Diagrams
100 100%
0% 0
Email
0 0%
100% 100
Flowcharts
100 100%
0% 0
Email Productivity
0 0%
100% 100

Questions & Answers

As answered by people managing Dia and ForthWrite.

Which are the primary technologies used for building your product?

ForthWrite's answer:

Next.js, React, Supabase, Anthropic Claude, OpenAI, Stripe, Vercel, Chrome Extensions API

What makes your product unique?

ForthWrite's answer:

ForthWrite learns your writing style from your actual sent mail, not a generic prompt. Every draft sounds like you wrote it because it was trained on how you actually write. It also auto-drafts replies before you open your inbox, so your email is partially handled before your day starts.

Why should a person choose your product over its competitors?

ForthWrite's answer:

Most AI email tools give you a blank box and a "write for me" button. ForthWrite builds a voice profile from your sent history and gets more accurate with every draft you edit or send. Unlike ChatGPT or Gemini, it works natively inside Gmail and Outlook with no copy-paste. Unlike Lavender, it writes the draft, not just scores it.

How would you describe the primary audience of your product?

ForthWrite's answer:

Professionals who send high volumes of relationship-critical email and cannot afford to sound generic: lawyers, financial advisors, recruiters, account executives, consultants, and founders managing their own inbox.

What's the story behind your product?

ForthWrite's answer:

Built out of frustration with AI writing tools that produce text that sounds nothing like the person sending it, and as a way to handle large amounts of daily email. The core insight was that your sent mail is the best training data you already have, and no tool was using it.

User comments

Share your experience with using Dia and ForthWrite. For example, how are they different and which one is better?
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Reviews

These are some of the external sources and on-site user reviews we've used to compare Dia and ForthWrite

Dia Reviews

10 Best Visio Alternatives for Cost Effective Diagramming [2022]
UI of Dia is not the best in the world. The icons have very low resolution, it does not have support for screen resolutions higher than 1080p so that users of large and Ultra wide monitors could have problems.
Best 8 Free Visual Paradigm Alternatives in 2022
Dia is a downloadable program that works with Windows and is a great way to make charts and diagrams just like with Visual Paradigm. The desktop tool provides different elements to make your chart more accurate. The tool also has a small learning curve which lets you start working on your projects after a few minutes of navigating. Dia is lightweight and runs smoothly on...
Source: gitmind.com
BEST 28 UML Tools in 2020
Dia is a full-featured diagramming program which is licensed under GPL. It allows you to draw various types of diagrams and has special objects to help you to draw ER diagrams, UML diagrams, flowcharts, network diagrams, and many other diagrams.
Source: www.guru99.com
40 Open Source, Free and Top Unified Modeling Language (UML) Tools
Pacestar UML Diagrammer helps users generate UML 2.0 diagrams quickly and easily. They can develop, document, and communicate their designs in a systematic yet flexible AND commonly understood notation. Also, they are able to create activity diagrams, class and object diagrams, communication diagrams, use case diagrams, sequence diagrams, state charts, package diagrams, and...

ForthWrite Reviews

  1. curtisboortz
    ยท Founder at ForthWrite ยท
    I built ForthWrite to fix generic AI email, and I still use it every day

    I built ForthWrite because I kept sending emails that sounded like they came from the same generic AI as everyone else. After launching it, I still use it for my own inbox every day, which is about the most honest endorsement I can give.

    The Chrome extension lives inside Gmail and Outlook on the web. Open a thread, hit Alt+Shift+D, and a draft comes back in your voice, not a template. The free tier is real: 10 drafts per week, no API key, no credit card. Voice matching is included on free, because that is the point.

    What keeps it useful compared to Gemini or a chat tab: it learns from what you actually send. Every edit you make before hitting send becomes a signal. Over time the drafts drift closer to how you really write, and the dashboard shows the improvement curve so you can see it happening.

    The web compose surface lets you draft from forthwrite.ai without installing anything, useful for people who want to try before committing to the extension.

    Standard adds recipient-aware and intent-aware drafting plus AI coaching. Pro adds auto-draft (replies waiting when you open Gmail), batch replies, and Prompt Lab for version-controlling your prompts. Teams adds a shared persona and seat-level analytics.

    ForthWrite is not for everyone. If you just need quick replies and tone does not matter, Gemini is free and already in your inbox. ForthWrite is for people where tone does matter: client communication, relationship-driven threads, external correspondence where sounding off costs something real.

    Disclosure: I am the founder and use it daily. Happy to answer questions in the comments.

    ๐Ÿ Competitors: Jace.ai, Fyxer, Mailmeteor
    ๐Ÿ‘ Pros:    Drafts land inside gmail and outlook; no copy-pasting from a chat window|Voice matching is on the free tier, not paywalled behind paid plans|No api key, no credit card to start; free tier runs on a server-side proxy|Learns from every edit you make before sending; drafts improve over time|Full keyboard flow: alt+shift+d to draft in any thread, no mouse required|Byok on paid plans, 9 providers supported, keys encrypted at rest|Web compose at forthwrite.ai works without installing the extension at all
    ๐Ÿ‘Ž Cons:    10 free drafts/week is enough to evaluate, not enough for a heavy inbox|Auto-draft, batch replies, and prompt lab all require the pro tier|Early-stage product; fewer third-party integrations than mature inbox tools|No mobile app: the extension and add-in are desktop-only (chrome on web, or the outlook desktop add-in)

Social recommendations and mentions

Based on our record, Dia seems to be more popular. It has been mentiond 12 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.

Dia mentions (12)

View more

ForthWrite mentions (0)

We have not tracked any mentions of ForthWrite yet. Tracking of ForthWrite recommendations started around Jun 2026.

What are some alternatives?

When comparing Dia and ForthWrite, you can also consider the following products

draw.io - Online diagramming application

ReclaimAI - Helps users prioritize their work and personal calendars

yEd - yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.

Superhuman - Superhuman is an email management tool.

LucidChart - LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.

Shortwave - Email smarter & faster with a reinvented experience for your Gmail