Software Alternatives, Accelerators & Startups

Undetectable.ai VS ForthWrite

Compare Undetectable.ai VS ForthWrite and see what are their differences

Undetectable.ai logo Undetectable.ai

The most powerful and advanced AI humanizer tool, built to bypass AI algorithms and ensure that your writing remains undetectable to AI detectors.

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.
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  • Undetectable.ai Homepage
    Homepage //
    2024-02-07

Undetectable.ai is an essential rewriting tool to detect and humanize your AI text from ChatGPT, Jasper, Copy.AI and similar AI tools into completely human-like content that avoids AI detectors.

  • 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.

Undetectable.ai

Pricing URL
-
$ Details
Platforms
-
Release Date
2023 May

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

Undetectable.ai features and specs

  • Advanced AI Detection Avoidance
    Undetectable.ai is designed to help users create content that is less likely to be flagged by AI detection systems, making it beneficial for users who need to ensure their content passes AI checks.
  • User-Friendly Interface
    The tool offers an intuitive and easy-to-navigate interface, making it accessible for users of various technical backgrounds to easily generate and modify text.
  • Versatile Use Cases
    Undetectable.ai can be employed for a wide range of applications, from content creation to academic work, where discretion and authenticity are critical.

Possible disadvantages of Undetectable.ai

  • Potential Ethical Concerns
    There are ethical implications associated with using technology designed to circumvent AI detection, as it may facilitate academic dishonesty or the spread of misinformation.
  • Dependency on Technology
    Users might develop a reliance on tools like Undetectable.ai to ensure their content is AI-safe, potentially diminishing their own skills in creating independently AI-resilient work.
  • Limited Accuracy Guarantee
    While it aims to bypass detection, there is no foolproof guarantee that content will remain completely undetectable across all current and future AI systems.

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

Undetectable.ai videos

๐Ÿ”ฅNEW Tool Beats Originality 10/10 [Undetectable.ai Review]

ForthWrite videos

No ForthWrite videos yet. You could help us improve this page by suggesting one.

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Category Popularity

0-100% (relative to Undetectable.ai and ForthWrite)
AI
97 97%
3% 3
Email
0 0%
100% 100
Writing Tools
97 97%
3% 3
Email Productivity
0 0%
100% 100

Questions & Answers

As answered by people managing Undetectable.ai 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 Undetectable.ai 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 Undetectable.ai and ForthWrite

Undetectable.ai Reviews

I Tested 5 AI Humanizers on the Same Essay โ€” Only One Passed All Detectors
The tools that work โ€” specifically HumanizeFast, and to a lesser extent Undetectable.ai โ€” take a fundamentally different approach. They don't just rewrite sentences. They restructure them, inject controlled randomness into word choice, vary sentence lengths intentionally, and break the structural patterns that detectors use as signals. They're not paraphrasing; they're...
Best AI Humanizer Tools Compared (2026): Free & Paid Options
If you prefer a more established platform, Undetectable.ai is the strongest alternative. Strong bypass performance, good mode variety, and a proven track record. The higher price and lack of a lifetime plan are the main drawbacks.

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, Undetectable.ai seems to be more popular. It has been mentiond 11 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.

Undetectable.ai mentions (11)

  • 10 Top Tools for Detecting AI Content
    Undetectable.ai is a powerful AI detector that analyzes text to determine whether it was generated by artificial intelligence. It stands out by offering a free AI detection tool with a multiple-scoring system, allowing users to see how different AI detectors evaluate their content. Unlike traditional detectors, it also provides rewriting capabilities, helping users refine AI-generated text to make it more... - Source: dev.to / over 1 year ago
  • Where Does ChatGPT Get Its Data From?
    AI detection tools are essential in maintaining the integrity and transparency of AI training data used by models like ChatGPT. These tools are intended to detect and address potential issues, including personal or sensitive data, biased content, or inaccuracies. - Source: dev.to / over 1 year ago
  • My essay gets flagged for AI even though I wrote it, advice?
    This is the website I used to check: https://undetectable.ai/. Source: over 2 years ago
  • Making LLama-2 Undetectable..?
    Basically, I want something similar to undetectable.ai, but built into oobabooga, or a similar "instruct" model that cannot be detected. Source: over 2 years ago
  • Weโ€™re the Chronicle of Higher Education, and weโ€™ve got expertise on ChatGPT in the classroom. Ask us anything.
    Running admissions essays through these types of checkers isn't advisable. Cases where AI detectors flag human writing as AI has been well documented, and a recent Stanford study showed that detectors are biased against English language learners. Itโ€™s also relatively easy to bypass AI detectors by rewriting the text or using tools like undetectable.ai. Source: about 3 years ago
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 Undetectable.ai and ForthWrite, you can also consider the following products

QuillBot - Quillbot is a free paraphrasing tool that will rewrite any sentence or paraphraph you give it. The article rewriter can rewrite essays or articles and is excellent as a grammar and fluency corrector.

Superhuman - Superhuman is an email management tool.

Humanize AI - Transform AI-generated text into natural, human-sounding content with Humanize AI. Perfect for students, marketers, bloggers, and writers who need polished, undetectable, and emotionally resonant writingโ€”fast, free, and easy to use.

Gemini - Gemini, formerly known as Bard, is a generative artificial intelligence chatbot developed by Google. Based on the large language model (LLM) of the same name, it was launched in 2023 in response to the rise of OpenAI's ChatGPT.

StealthGPT - A tool to create content that bypasses ai detection

Lavender - Realtime coaching for sales emails.