Boost Email Opens With AI in Seconds

What it does

TestMySubject is a free AI tool that helps you write better email subject lines. Just drop in your subject line and it scores it, critiques it, and gives you 3 improved AI rewrites instantly.

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  MailTester.AI2025 · mailtester.ai · ▲327

  Forward an email and get an AI deliverability report in 30s

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  Free AI Email Subject Line Generator2021 · encharge.io · ▲174

  Create impactful unique subject lines using AI and GPT-3

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  AI Subject Line Generator2023 · ecosend.io · ▲96

  Generate a brilliant subject line in seconds, with GPT

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  Email Subject Line Generator2023 · subjectlinegenerator.com · ▲130

  Instantly generate catchy email subject lines

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  EzMail.AI2023 · ▲115

  Reply to emails 10X faster with pre-filled drafts by AI

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  Free AI Email Assistant2024 · ▲121

  Forward, add context, generate 👉 no more boring replies

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  WallHop – 12ft.io is gone, so I built a replacement▲287

  wallhop is a free paywall bypass. Paste any article link to read it without paywall popups, ads or clutter. No signup, no extension. A simple 12ft.io alternative.

  Growth · 11d ago · wallhop.io

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  Prefer▲201

  The execution layer for AEO

  Growth · 23d ago · tryprefer.com

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  MakerMap▲197

  A living map of makers and what they’re building

  Growth · 26d ago · makermap.lol

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  I'm an airline pilot – I built interactive graphs/globes of my flights▲1,539

  Hey HN! Pilots everywhere are required to keep a logbook of all their flying hours, aircraft, airports, and so on. Since I track everything digitally (some people still just use paper logbooks!), I put together some data visualizations and a few 3D globes to show my flying history. This globe is probably my favourite so far: https://jameshard.ing/pilot/globes/all If you’ve got ideas for other graphs or ways to show this kind of data, I’d love to hear them!

  Life & fun · 2025 · jameshard.ing

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  Chronicle: Cursor for Slides▲1,212

  Stunning presentations with AI. No design skills required.

  AI · 2025 · chroniclehq.com

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  Bubble for native mobile apps (beta)▲1,026

  Build native mobile apps for iOS and Android without code.

  Dev tools · 2025 · bble.io

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  Twenty▲989

  Build your Enterprise CRM with an AI-friendly SDK

  Dev tools · 2025 · twenty.com

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  Pally - AI Relationship Management▲949

  All your connections, across all your socials.

  AI · 2025 · pally.com

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  Workout.cool – Open-source fitness coaching platform▲827

  I was the main contributor to workout.lol, an open-source fitness app to easily build a workout routine. The project had traction (1.4k GitHub stars, 95 forks, ~20K visits/month), but was eventually sold due to video licensing hurdles. The new owner stopped maintaining it, and the repo went abandoned. Over the next 9 months, I sent 15 emails to try to save it : no replies. Feature requests & issues were ignored. The community was left with a "broken" tool let's say. I couldn't just let it die So I built the new version from scratch with the same open-source spirit, but a better…

  Dev tools · 2025 · github.com