What you can do here
These calculators are designed for real decisions rather than toy arithmetic. They help with money, grades, room planning, calories, timing, and day-to-day comparisons.
Calculators
Free online calculators for everyday math and conversions.
10 tools in this category
← HomeWho this category helps
Useful for students, freelancers, households, job seekers, and anyone who wants a clean answer without opening a spreadsheet or signing up for an app.
How to choose the right tool
Choose the calculator closest to your decision: Salary, Tip, Net Worth, Invoice, GPA, TDEE, or Reading Time. Most pages explain the result immediately so you can act on it.
Popular starting points
If you are deciding how much, how long, or what target to aim for, start with the calculator that maps directly to that decision.
Aspect Ratio Calculator
Calculate aspect ratios instantly. Convert dimensions, solve for missing sides, and browse 2025/2026 social media image sizes.
Salary Calculator
Convert salary to hourly rate instantly. Calculate annual, monthly, weekly, daily, and hourly pay with configurable working hours and leave days.
Tip Calculator
Calculate tips and split bills instantly. Supports HK 10% service charge toggle, custom tip %, and per-person split with WhatsApp sharing.
Aspect Ratio Calculator
Calculate aspect ratios instantly. Convert dimensions, solve for missing sides, and browse 2025/2026 social media image sizes.
Salary Calculator
Convert salary to hourly rate instantly. Calculate annual, monthly, weekly, daily, and hourly pay with configurable working hours and leave days.
Tip Calculator
Calculate tips and split bills instantly. Supports HK 10% service charge toggle, custom tip %, and per-person split with WhatsApp sharing.
GPA / Final Grade Calculator
Calculate the final exam score you need, run GPA what-if scenarios across multiple grading systems, and export a verdict card locally.
Floor Plan Tool
Lay out a room in 2D, drag furniture into place, rotate selected items, and export a clean PNG with no account or watermark.
Invoice Generator
Create a client-ready invoice with your branding, taxes, and line items, keep drafts locally, and download a clean PDF with no watermark.
Net Worth Tracker
Track assets, liabilities, and net worth locally with HK-friendly fields, automatic history snapshots, and CSV export.
TDEE Calculator
Estimate your daily calories with Mifflin-St Jeor, compare Harris-Benedict, and get macro targets you can bookmark.
ADHD Task Prioritiser
Paste your task list, answer three low-friction questions, and get one next task to do right now.
Cover Letter Builder
Build a tailored cover letter with three templates, instant preview, and PDF download in your browser.