File, document and everyday web utilities
Online calculators and math tools
Browser and mobile calculators, calculator collections, and math practice or solving apps for everyday calculations, students, and learners building math skills.
Built for: General public and math students
Projects since May 04
156
Different builders
147
Last 4 weeks vs 8 before
▲ +37%
AI is the core
8.3%
Projects per week
Mostly web app (60%), mobile app (26%), browser extension (4.5%) · from r/SideProject, r/vibecoding, r/IMadeThis, r/ShowYourApp
Latest
- AURA Global Tools — Provides a collection of 300+ free online calculators and utilities covering Islamic, finance, and health topics, with no sign-up required.“Do whatever you want to do, I won't tell you not to do this or that.”
- Math&More AI — Provides an iOS app for math and productivity tasks using AI.“Math&More Ai”
- KittyCalc — Performs arithmetic calculations on a custom-built physical calculator device.“Built a hardware calculator from scratch in pure C”
- kinetic — Displays interactive animated visualizations of math and physics concepts in the browser.“I'm making a collection of interactive math/physics visuals, open-source”
- Engramlabz — Turns a typed maths question into a narrated, animated vector video explainer with captions.“I built an app that turns maths questions into animated explainers for ~﹩1 each | Example: 23 people, 50.7% chance two share a birthday”
- US Life Toolkit — Provides 36 free everyday calculators for US-specific math such as mortgages, rent vs. buy, moving costs, and party food quantities, computed locally in the browser.“I built a collection of 36 free calculators for everyday life in the US — no signup, runs locally in your browser”
- Notena — Calculates a German high school student's running grade average from subject grades, weighted by subject and exam type.“I'm 17 and built a grade calculator for German high schoolers because nobody knows their own GPA until report cards arrive”
- Types or speaks math input and draws it on screen through a virtual Windows pen so it appears on any whiteboard app.“Wrist pain from online whiteboards, so I built an app to write for me”
- Fruity Math — Lets kids practice math facts by saying answers aloud to slice fruit in a Fruit Ninja style game.“Fruity Math - a voice based game for learning math facts on iOS”
- Calculyn — Provides over 110 free online calculators for finance, home, health, math, everyday life and unit conversions in one website.“I created an all encompassing calculator website called Calculyn.”
- areweai — Presents an animated story and interactive browser version that explore whether the world and human thought are mathematical, with hoverable math explanations in 10 languages.“is the world basically one giant algorithm? and if we're part of it, are we just math too, so kind of AIs?”
- Pythos — Answers math and physics questions with an LLM whose mathematical claims are checked by deterministic tools before delivery, withholding answers that fail verification.“I built an AI math/physics tutor that verifies the LLM's answers before delivering them — 110K blind problems, 0 incorrect delivered”
- Bundles several everyday calculators into one Android app.“I built an Android calculator app that puts several everyday calculators in one place”
- SyneIOS — Provides a calculator toolbox for everyday maths on iOS.“SyneIOS: a toolbox for your everyday maths”
- ProofWatch — Tracks papers, posts and comments about major open math and CS problems and labels unverified breakthrough rumors.“ProofWatch — a free tracker for big math/CS problems and breakthrough rumors”
- CalculatorWoosh — Provides a collection of free everyday calculators that work without account sign-up.“I built a free calculator website — CalculatorWoosh”
- Number Legend — Provides 25+ browser-based calculators and converters, such as BMI, mortgage, percentage, age, unit conversion, and word count.“I built a free calculator site with 25+ tools — from my phone, in Pakistan”
- MathIQ — Provides an AI tutor that helps students work through college-level math problems.“MathIQ”
- Fizz-Buzz — Plays the fizz-buzz counting game, replacing multiples of 3 and 5 with words.“First App: Fizz-Buzz!”
- Performs symbolic math calculations with units, graphs, solving, calculus and matrices in a notebook-style worksheet app on iPhone and Mac.“I couldn’t find a good free CAS calculator for iPhone, so I built one”
Most discussed
- CameraAIBoard — Lets users draw math equations in the air with a finger via webcam, then uses AI to solve them and write the answer back as handwriting.“Weekend project: draw math in the air with your finger, AI solves it on the board”
- Number Ninja — Gamifies math homework for kids with characters, power-ups and maps to unlock, and shows parents which questions were missed.“I vibecoded an app that is for just one person, the most important person in my world.”
- Converctor — Provides a collection of simple converters and everyday calculation tools in one website.“I built a website, launched it, and so far it has made exactly R$0”
- ADDR — Adds two numbers through a multi-stage pipeline with AI review and a written assessment of the sum.“u/RefrigeratorKey8555 asked for this 5 days ago. I built it.”
- Freedom Units: the America Calculator — Converts between metric and US units and humorously converts measurements into American symbols.“Aaaaaand I’m on app on the App Store”
- discovery-loop — Runs an evolutionary program search overnight on open math problems, checking each candidate solution against an automated verifier.“I vibecoded my way to a math record and my OpenClaw agent was cited as a contributor”
- areweai — Presents an animated story and interactive browser version that explore whether the world and human thought are mathematical, with hoverable math explanations in 10 languages.“is the world basically one giant algorithm? and if we're part of it, are we just math too, so kind of AIs?”
- NotGPT — Answers chat-style queries like unit conversions and percentages using rules, regex and traditional NLP instead of an LLM.“I made a weird little project - NotGPT”
- Slice of Pi — Lets users type a four-digit number and visualizes its location within the first 250,000 digits of pi in a 3D dot sphere.“I didn't hide your birthday inside π. It was already there. I just built the spaceship.”
- Calculator — Lets users restyle a calculator app's full interface with themes, colors, and fonts, including animated designs.“Calculator - A Calculator You Can Restyle”