Show HN: I made a web-based notepad with a built in unit calculator

1

Calca

I've found that the Calca[†] format hits a nice sweet spot between using an ordinary calculator and running a spreadsheet. [†]: http://calca.io It's particularly suited to calculations I'm doing by fetching various numbers from websites, and for the most part it 'composes' by just copypasting a calca into another one. Basically where the numbers mean something, aren't stable / I don't know them all when I start, but there's no tabular data or significant aggregation going into the question.

#Calculator #Advanced Calculator #Productivity 18 social mentions

2

Soulver 3 for Mac

This looks pretty cool. I've long been looking for something similar to Soulver (https://soulver.app/) that I can use on Linux. This seems promising. One small criticism: In my opinion, no web-based writing app is useful unless the tab key inserts a tab. The default behavior of most browsers to move focus to the next field is tremendously infuriating in this context. Unfortunately, that's what happens here, at least for Firefox. (Related: key combinations that normally perform cursor movements but which are often used by browser for navigation.).

#Calculator #Advanced Calculator #Productivity 30 social mentions

3

Numi App

Very nice! Reminds me a lot of numi (https://numi.app). Similar, but MacOS only (and paid).

#Calculator #Advanced Calculator #Text Calculator 29 social mentions

4

Numbr

I've never used Soulver, but there is a free web app https://numbr.dev that seems very similar to it.

#Productivity #Calculator #Online Calculators 10 social mentions

5

Frink

See also Frink: https://frinklang.org/ > Frink is a practical calculating tool and programming language designed to make physical calculations simple, to help ensure that answers come out right, and to make a tool that's really useful in the real world. It tracks units of measure (feet, meters, kilograms, watts, etc.) through all calculations, allowing you to mix units of measure transparently, and helps you easily verify that your answers make sense. It also contains a large data file of physical quantities...

#Calculator #Advanced Calculator #Engineering Calculator 26 social mentions

6

Insect

I'm surprised no one mentioned https://insect.sh yet.

#Calculator #Advanced Calculator #Engineering Calculator 9 social mentions

7

Math.js

Ha, yes, I was being nosy. It was quite easy to spot as it's the only XHR/Fetch request. I was intrigued what you had used to build it, and if you had built your own solver (which you have), and what editor you used (Code Mirror) so went looking at the code. Interesting to see you left the source maps for production, made it easy for my sleuthing... I experimented with a similar idea last year, but used ProseMirror/TipTap as the editor to enable rich text editing, and the MathJS (https://mathjs.org) solver. I also combined it with PouchDB and Yjs for offline editing and syncing between devices. Never finished it though, you have kept your nice and simple!

#Calculator #Development Tools #Productivity 19 social mentions

8

Joplin

That's really cool! Anyone knows if there's a way to have this feature in Joplin[0] ? [0]: https://joplinapp.org/.

#Note Taking #Notes #Todos 350 social mentions

9

Qalculate!

Note: I had this response typed up but didn't submit... One related app that I absolutely love is Qalculate![1] (yes, it has a built-in exclamation for default enthusiasm :) ) It can do cool stuff like converting N (newtons) to kg.m/s^2 when you specify units as ?kg. It also converts units like 1kW x 1year = 31.55... GJ It's fantastic for engineering and specially back-of-envelope calculations. This notepad aspect does seem useful though. One alternative is to use Jupyter notebooks, sometimes I work problems with Sage[2]+Jupyter. Sage is extremely powerful (you can do calculus, linear algebra, and more) but doesn't support units (that I know of), it's more geared toward advanced maths. [1] https://qalculate.github.io/ [2] https://www.sagemath.org/ It's a bit on the heavy side although it's definitely worth it if you're doing a lot of math. I think the flatpak is preferred due to its significant size.

#Calculator #Advanced Calculator #Engineering Calculator 31 social mentions