Rise Time & Bandwidth Calculator

Convert between signal Rise Time (10% to 90%) and analog Bandwidth using the standard 0.35 rule.

Calculation Type

Quick Guide

The 0.35 Rule

BW = 0.35 / tr
This is an approximation valid for single-pole low-pass filter responses (like an RC circuit), which accurately models many front-ends of oscilloscopes and basic amplifier stages.

Oscilloscope Rule of Thumb

To accurately measure the rise time of a signal, the bandwidth of your oscilloscope should be at least 3 to 5 times larger than the bandwidth of the signal being measured. A 100MHz scope has an internal rise time of about 3.5 ns.