Math you
finally understand.
CalcSim AI was born from a real frustration: tools that solve the calculation but don't explain the why. We built a calculator that teaches — and a library that doesn't charge you to learn.
Mission
Why does CalcSim AI exist?
Truly free
The calculator and library are free. No content paywall, no aggressive ads, no unnecessary data collection.
Made in Brazil
Accessible language, real-world examples, financial math with interest rates and local investment products.
Education, not entertainment
The goal is not to keep you in the app — it's to make you understand. An explanation that makes the next search unnecessary is the biggest success.
Features
Everything the app offers
Scientific calculator
Full scientific mode, DEG/RAD, linear equations and the Financial Calculator for TVM, NPV and IRR calculations.
Smart OCR
Point the camera at any math expression — handwritten, in a book or typed — and the app solves it instantly.
AI explanation
Not just solving: the AI explains the concept behind each calculation, in plain language, with context that makes sense to you.
Free library
Over 37 articles on math from beginner to advanced, all free and without sign-up, directly on the portal.
AI Professor
AI chat specialised in math. Ask questions, request exercises, explore topics of your interest.
Synced history
All your calculations saved and synced across devices via Google account. Never lose a result.
The team
Renato Freitas
Founder & developer
Brazilian developer passionate about education and technology. CalcSim AI is an independent project built on the belief that quality tools should not be a privilege for those who can pay. The entire app — from Flutter to Firebase, Cloud Functions to the Next.js portal — is built and maintained by me.
The project
CalcSim AI in numbers
37+
Published articles
8
Math categories
AI
OCR + Chat + Explanation
100%
Free to learn
Contact
Get in touch
Suggestions, bugs, partnerships or just want to say hi — every message is read personally.
Explore CalcSim AI