Feed rate calculator

Calculate the feed rate for CNC machining operations based on cutting speed, spindle speed, and tool diameter

Input Parameters

Surface Feet per Minute (sfm)

Revolutions Per Minute (RPM)

Tool diameter in inches

Calculation Results

Feed Rate (ipm)

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Inches per Minute (ipm)

Calculation Formula

Feed Rate (ipm) = (π × Tool Diameter × Spindle Speed) / 12

Where:
π ≈ 3.14159
Tool Diameter: Diameter of the cutting tool in inches
Spindle Speed: Speed of the spindle in RPM
12: Conversion factor from feet to inches

Feed rate calculator Calculator Usage Guide

Learn how to use the Feed rate calculator calculator and its working principles

How to use the calculator

  1. Enter the Cutting Speed (sfm) - the surface speed at which the tool cuts the material.
  2. Enter the Spindle Speed (RPM) - how fast the spindle rotates.
  3. Enter the Tool Diameter (inches) - the diameter of your cutting tool.
  4. Click the Calculate button to compute the feed rate.
  5. Use the Reset button to clear all inputs and start over.

Understanding Feed Rate

The feed rate is the speed at which the cutting tool moves through the material. It's an important parameter in CNC machining that affects the surface finish, tool life, and cutting efficiency.

Example Calculation

Suppose you have a tool with a diameter of 0.5 inches, and you want to run it at 3000 RPM. If you're using a cutting speed of 200 sfm, the feed rate would be calculated as:

Feed Rate = (π × 0.5 × 3000) / 12 ≈ 392.7 ipm

Important Considerations

  • The cutting speed depends on the material being cut and the tool material.
  • Always consult the tool manufacturer's recommendations for optimal cutting parameters.
  • Too high feed rate can cause tool breakage, poor surface finish, and material damage.
  • Too low feed rate can lead to inefficient cutting and overheating of the tool.