19 free engineering calculators
for electronics, geometry and code.19 free engineering calculators
for electronics, geometry and code.Free · No sign-up · Works in your browser
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Electronics Voltage Divider 
Series resistor networks, solved live. Real-time computation of series resistor networks with schematic visualization. Solve R1, R2 or Vout from the other two. Electronics Resistor Codes 
4 and 5-band color code decoder. IEC 60062 standard decoder for 4 and 5-band resistors, with the tolerance range and one-tap presets for common values. Electronics Ohm's Law Calculator 
V, I or R from the other two, plus power. Enter any two of voltage, current and resistance to get the third, plus the power dissipated. Electronics Series & Parallel Calculator 
Series and parallel networks, drawn. Place and arrange resistors and batteries in series or parallel to instantly calculate equivalent resistance and total voltage. Electronics LED Calculator 
Series resistor, PWM and Arduino code. Calculate the LED series resistor, pick standard colors with forward voltages, simulate Arduino PWM brightness and generate ready-to-use code. Electronics LCD Designer 
HD44780 screens and custom characters. Design HD44780 LCD screens visually. Create custom characters, preview in real time and generate Arduino code for 16×2 and 20×4 displays. Electronics Power Station Runtime 
Battery runtime for any set of devices. Add the devices you plan to run and see how long the battery actually lasts, for any combination of loads. Geometry Circle Solver 
Radius, diameter, circumference, area. Bidirectional calculation of radius, diameter, circumference and area from whichever one you know, with visual feedback. Geometry Rectangle Solver 
Area, perimeter and diagonal. Calculate area, perimeter and diagonal length instantly from the side lengths, drawn to scale. Geometry Square Solver 
Side, diagonal and area from one input. Compute side length, diagonal, perimeter and area from a single measurement. Geometry Pythagorean Theorem 
The third side of any right triangle. Enter any two sides of a right triangle to calculate the third side, all angles, area and perimeter with animated visualization. Programming Binary Converter 
Decimal and binary, step by step. Convert between decimal and binary with step-by-step explanations and byte limit visualization. Programming Hexadecimal Converter 
Hex, decimal, binary and octal. Convert seamlessly between hexadecimal, binary, decimal and octal number systems with real-time visualization. Programming Bitwise Calculator 
AND, OR, XOR and NOT, bit by bit. Perform bitwise operations (AND, OR, XOR, NOT) with visual representation and detailed step-by-step explanations. Programming Median Calculator 
Median of any dataset, even or odd. Calculate the median of up to 50 values with automatic even/odd detection, a step-by-step explanation and the code to reproduce it. Math & Utilities Matrix Calculator 
2×2 to 5×5, ten operations. Add, subtract, multiply, scale and power matrices, plus determinant, inverse, transpose, trace and rank. 2×2 to 5×5 with a visual grid editor. Math & Utilities Percentage 
X% of Y, change, markup, discount. All-in-one percentage tool: X% of Y, what percent, percentage change, markup and discount, with donut chart and bar visualization. Math & Utilities Unit Converter 
Length, mass, temperature and more. Convert length, area, volume, mass, temperature, power and pressure with instant results across all common units. Math & Utilities Gear Ratio 
Ratio, output RPM and torque. Calculate gear ratio, output RPM and torque from tooth counts. Animated meshing gears with real-time speed visualization.