Free Toolkit

Image ThresholdConvert images to pure black and white using adjustable threshold.

Image Threshold illustration
🖼️

Image Threshold

Convert images to pure black and white using adjustable threshold.

How to Use
1

Upload Image

Drop or select an image.

2

Set Threshold

Adjust the brightness cutoff point.

3

Apply and Download

Click Apply, preview, and download.

What Is Image Threshold?

Converts images to pure black and white. Pixels brighter than the threshold become white (255), darker become black (0).

Why Use Our Image Threshold?

  • Adjustable threshold
  • Clean binary output
  • Useful for OCR preprocessing
  • Fast per-pixel operation

Common Use Cases

Document Cleanup

Clean scanned documents.

Stencil Creation

Generate black-and-white stencils.

Logo Extraction

Isolate logos from backgrounds.

Shadow Art

Create silhouette art from photos.

Technical Guide

Luminance = R*0.299 + G*0.587 + B*0.114. If luminance >= threshold: 255, else 0.

Tips & Best Practices

  • 1
    Start at 128 and adjust
  • 2
    Lower = more white
  • 3
    Higher = more black
  • 4
    160-200 for text extraction

Related Tools

Frequently Asked Questions

QSame as grayscale?
No — grayscale has 256 shades; threshold has only black and white.
QRight threshold?
Start at 128. For documents try 160-200.
QWhat is luminance?
R*0.299+G*0.587+B*0.114, matching human brightness perception.
QPer-channel threshold?
This uses combined luminance.

About Image Threshold

Image Threshold is a free online tool from FreeToolkit.ai. All processing happens directly in your browser — your data never leaves your device. No registration required. No ads. Just fast, reliable tools.