Cross your he.art

What it does

Solve those pesky ratios with ease using Cross Your Heart, the ultimate cross-multiplication tool. No more frustration or math anxiety - just accurate answers at the click of a button.

Calculate a cross-multiplication without picking up a pen.

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  I made an interactive math crossword puzzle with infinite levels2024 · scientific.place · ▲165

  Hey there! I'm the brains behind the math crossword game on my site. This game is all about making math a little more fun – users just drag and drop numbers to fill in the blanks and move on to the next level if they get it right. Let me know if face any issues or have any suggestions! :)

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  I made a web game that makes practicing basic arithmetic fun2024 · worchle.com · ▲161

  Hey, maker here. After launching a daily word search game, I randomly thought of this math game while driving. Finally got around to making it and I think it turned out pretty cool. It’s a math search game that’s meant to help you practice your quick addition, subtraction, multiplication, and division skills. I’m hoping it’ll help people (even those like me who aren’t big on math) learn and increase their speeds. (There are also some settings you can enable to make the game harder) If you try it out, please let me know if you found it fun, if you have anything you’d like me to add, or if you…

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  QkMath.com2022 · qkmath.com · ▲72

  Mathematics for everyone

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  Tip Calculator2021 · tipcalc.net · ▲73

  The ultimate tip calculator with split function

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  MathCrossProf2025 · play.google.com · ▲11

  Train your brain daily with unique math crossword puzzles.

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  Crossnumber2025 · apps.apple.com · ▲7

  Find Numbers, Math Puzzle

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  /dev/null▲486

  a social network for devs

  Dev tools · 3d ago · dev-null.sh

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  Whiteboard (YC W26) – an open-source IDE for thoughtful software design▲423

  open-source IDE for thoughtful software design. Contribute to devdotfast/whiteboard development by creating an account on GitHub.

  Dev tools · 28d ago · github.com

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  Reladraw – A diagram language where you decide where to place things▲411

  Contribute to reladraw/reladraw development by creating an account on GitHub.

  Dev tools · 26d ago · github.com

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  OpenBot▲362

  Grok Bot alternative: free, local, open-source, multiplayer

  Dev tools · 23d ago · openbot.run

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  Talanoa▲346

  Hi HN, I’m a fullstack developer, and honestly, I’ve lost count of how many side projects I’ve worked on over the years. But one idea kept coming back to me: a different kind of email client. It first came to me in 2014: “What if we could handle emails more like conversations?” Every year, I’d revisit this concept in my “Build Notes.” Ten years later, no one had built exactly what I had in mind — so I finally decided to do it myself. That’s how Talanoa was born. I wanted something focused on people, not timelines. I was tired of marking messages as unread just to remember to reply later, or…

  Dev tools · 21d ago · talanoa.email

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  CoreSpeed▲332

  One MCP for everything your agents need: apps, memory, tools

  Dev tools · 28d ago · corespeed.io

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  New AI edits images based on text instructions▲1,098

  This works suprisingly well. Just give it instructions like "make it winter" or "remove the cars" and the photo is altered. Here are some examples of transformations it can make: Golden gate bridge: https://raw.githubusercontent.com/brycedrennan/imaginAIry/ma... Girl with a pearl earring: https://raw.githubusercontent.com/brycedrennan/imaginAIry/ma... I integrated this new InstructPix2Pix model into imaginAIry (python library) so it's easy to use for python developers.

  AI · 2023 · github.com

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  HyperSwitch▲715

  Fast, reliable, and affordable open source payments switch

  Dev tools · 2023 · hyperswitch.io

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  I've built a C# IDE, Runtime, and AppStore inside Excel▲670

  The project is called QueryStorm. It uses Roslyn to offer C# (and VB.NET) support in Excel, as an alternative to VBA. I've posted about it before, but a lot has changed since then so figured I'd share an update. The current version includes a host of new features, namely a C# debugger, support for NuGet packages, and the ability to publish Excel extensions to an "AppStore" (which is essentially a NuGet repository). The AppStore can be used by anyone with the (free) runtime component. Another great addition is the community license, which is a free license for individuals and small companies…

  Work · 2023 · querystorm.com

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  I'm a doctor and made a responsive breathing app for stress and anxiety▲666

  Hey HN! Some more info: I’m an NHS doctor and the founder of Pi-A (https://www.pi-a.io) which developed Lungy (https://www.lungy.app). Lungy is an app (iOS only for now) that responds to breathing in real-time and was designed to make breathing exercises more engaging and beneficial to do. It hopefully has many aspects of interest to the HN community – real-time fluid, cloth and soft body sims running on the phone’s GPU. My background is as a junior surgical trainee and I started building Lungy in 2020 during the first COVID lockdown in London. During COVID, there were…

  Life & fun · 2023 · lungy.app

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  Product Hunt Rewind 2022▲620

  Your 2022 on Product Hunt

  Life & fun · 2023

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  LaunchPedia▲616

  200+ handpicked tools to skyrocket your product launch

  Growth · 2023 · launchpedia.co