Playful learning for kids. Get the App!
TeddyBase is a playful educational app for iPhone and iPad, developed by calkoo.com team — perfect for kids and families to explore, learn, and imagine together! Learn colours, letters, shapes and more!
Capital Budgeting
Cost of Capital
Measurement & conversion
- 101Binary Converter
- Body Height or Weight Converter
- local_diningCooking Units
- ¥€$Currency and SDR Converter
- euro_symbolEuro Calculator (Latvia)
- euro_symbolEuro Calculator (Lithuania)
- local_gas_stationFuel Cost Calculator
- HEXHexadecimal Converter
- XIVRoman Numerals Converter
- Shoe Size Converter
- cachedUnit Converter
Physics
Chemistry
For residents of Estonia 
- euro_symbolEEK-EUR Conversion Calculator (Estonia)
- Estonian Motor Vehicle Tax Calculator
- check_boxFringe Benefit (Estonia)
- poolHoliday Pay (Estonia)
- child_friendlyParental Benefit (Estonia)
- Salary/Wage and Taxes 2025 (Estonia)
- Sickness Benefit (Estonia)
- 0%Tax-Free Income (Basic Exemption - Estonia)
- monetization_onTaxation of Dividends (Estonia)
Taxes
Date and Time
Time Value of Money
Financial analysis
Finance
Saving & investing
Health
Fitness
Conversion of Units
- AConversion of Acceleration Units
- αConversion of Angle Units
- m2Conversion of Area Units
- GBConversion of Data Storage Units
- ρConversion of Density Units
- EConversion of Energy Units
- FConversion of Force Units
- local_gas_stationConversion of Fuel Units
- mConversion of Length Units
- PConversion of Power Units
- pConversion of Pressure Units
- vConversion of Speed Units
- C°Conversion of Temperature Units
- tConversion of Time Units
- τConversion of Torque Units
- VConversion of Volume Units
- mConversion of Weight and Mass Units
Stock Analysis
Loan & leasing
Real estate
Mathematics
- categoryArea Calculator
- △Area, circumference, angles of a triangle
- Calculation of Percentage
- panorama_fish_eyeCircle
- X%Common Fraction to Percentage
- ¾Common Fractions
- logExponentiation, Logarithm, Nth root
- 2¼Fraction to Decimal Conversion
- φGolden Ratio
- XProportion: Cross-Multiplication
- C²Pythagorean Theorem
- X²Quadratic Equation
- 45°Trigonometry
- B/AVieta's formulas (for quadratic equation)
- Volume Calculator
Geometry: Area and Surface Area
- Area of a Circle
- Area of a Parallelogram and Rhombus
- Area of a Regular Polygon
- Area of a Sector
- Area of a Square and Rectangle
- Area of a Trapezoid/Trapezium
- Area of a Triangle
- Area of a Triangle (Heron's Formula)
- Area of an Ellipse
- Surface of a Cone
- Surface of a Cube
- Surface of a Cylinder
- Surface of a Rectangular Cuboid
- Surface of a Regular Tetrahedron
- Surface of a Sphere
Geometry: Volume
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