Show HN: Mathpad – Physical keypad for typing 100+ math symbols anywhere
10 comments
·August 2, 2025staplung
Very cool. I've long wanted something that's a bit of a cross between a calculator and a numpad; something that could be used as a calculator or just to send symbols to the computer that are easier to type on such a device.
Question: the description says it has access to all the Greek alphabet letters but only the lower case ones are shown on the keypad: do you get (e.g. ∆) by using the shift key on the regular keyboard plus δ on the Mathpad?
toomuchtodo
I think this is super cool and intend to donate because I love the love and thought you’ve put into this. With that said, did you consider using something like an Elgato Stream Deck programmable control pad?
MagneLauritzen
Thank you for the kind words. I did orginally consider using a programmable stream deck, but quickly realized that it would not be sufficient. My requirements were:
1) Over 100 symbols immediately accessible
2) Single-hand use
3) Small size
The elgato stream deck meets some of these requirements, but it would not have been possible to support the amount of symbols I wanted.
olejorgenb
1. Cool!
2. Why use a staggered layout? Because people are used to it? Counterpoint: the numpad is not staggered and people are easily able to use both parts of a normal keyboard)
MagneLauritzen
1) Thank you!
2) The staggered layout has been carefully chosen to allow for single-hand use. The user must be able to press up to three keys at the same time (2 modifiers and 1 symbol key). The layout I settled on for Mathpad makes this as easy as possible.
olejorgenb
Interesting. Perhaps the fingers do want to go at a slight angle so making it a good choice :)
tonetegeatinst
Amazing project and glad to see something like this exits. While my current setup dosnt allow for this, if that ever changes and I start taking more latex notes I will be ordering one of these.
MagneLauritzen
Thank you!
The killer feature of Mathpad is not LaTeX (although that is supported) - it's letting you directly type mathematical Unicode symbols practically anywhere you can type regular text.
Mathpad will remain available on Crowd Supply long after the campaign ends (albeit at a higher price), so just come back later when you need one!
westurner
How much faster is Mathpad than creating a per-document table of symbols with their Unicode numbers and/or latex values and copy/pasting until you remember the Ctrl-Shift-u nnnn sequence?
MagneLauritzen
Not much faster if you only need a few symbols, and if you only work in one document. I used to make such tables for large documents before I created Mathpad.
Mathpad's killer feature is working anywhere you can type text, not only document editors. I've found it particularly useful when putting together technical presentations in Powerpoint, and when documenting the algorithms I write at work which are rather math and physics heavy.
Here's something different than your usual fare: A physical keypad that lets you directly type math!
Ever tried typing mathematical equations in your code IDE, email, or on Slack? You might know it can be tricky. Mathpad solves this with dedicated keys for Greek letters, calculus symbols, and more. Press the ∫ key and get ∫, in any application that accepts text. It uses Unicode composition, so it works everywhere: Browsers, chat apps, code editors, Word, you name it. Basically, anywhere you can type text, Mathpad lets you type mathematics.
I built Mathpad after getting frustrated with the friction of typing equations in e.g. Word, and what a pain in the ass it was to find the specific symbols I needed. I assumed that a product like Mathpad already existed, but that was not true and I had to build it myself.
It turned out to be pretty useful! Three years of solo development later, I'm launching on Crowd Supply. One of the trickiest parts of this project was finding someone who could manufacture custom keycaps with mathematical symbols. Shoutout to Loic at 3dkeycap.com for making it possible!
Fully open source (hardware + software): https://github.com/Summa-Cogni/Mathpad Campaign: https://www.crowdsupply.com/summa-cogni/mathpad Project log: https://hackaday.io/project/186205-mathpad-the-math-keypad