Pull-up / Pull-down Resistor Calculator

Calculate the optimal resistor value, valid range, current draw, and power dissipation for pull-up or pull-down configurations.

Configuration

Choose pull-up or pull-down mode

Logic Family Presets

Input Values

Pull-Up Circuit

VccRPinto switch/open drain

Analysis

✓ Value is in valid range
Valid range: 165 Ω — 1300000 Ω
Suggested Range200 – 1,299,000 Ω
Current (when driven)0.330 mA
Power Dissipation1.089 mW
Pin Voltage (floating HIGH)3.2900 V
Pin Voltage (driven LOW)0.0100 V

Quick Guide

Typical Values:

General GPIO4.7 kΩ – 10 kΩ
I²C Bus (100 kHz)4.7 kΩ
I²C Bus (400 kHz)2.2 kΩ
SPI Chip Select10 kΩ
Reset Lines10 kΩ
Buttons / Switches10 kΩ

Tips:

  • Lower R → faster rise/fall time but higher current draw
  • Higher R → lower power but slower signal edges and more noise susceptibility
  • For I²C, calculate based on bus capacitance and speed
  • Always check your MCU datasheet for VIH, VIL, and IIL