CruxDevCruxDev Tools Studio Prompts
image Utility • Zero-Server Privacy • 100% Client-Side

Remove Image Background (colour-based)

Make a plain or green-screen background transparent by colour, with tolerance and soft edges. Flood fill from the edges or click points, or remove every matching pixel. Not AI: made for solid backdrops.

Overview

Removes a solid or near-solid background from an image by colour and saves a transparent PNG. It suits product shots on white, logos, scanned signatures, screenshots and green screen. Set the key colour, tolerance and edge softness, and choose whether to remove only background connected to the edges or every matching pixel. It is not AI segmentation, and the page says so.

How It Works

Drop an image and the tool guesses the background colour from the most common colour along the border. Adjust Tolerance to include similar shades and Edge softness to fade the boundary instead of cutting it hard. In Connected mode the fill starts from the four corners; click the preview to add more fill points, or switch the click to pick the key colour from the image. Every matching pixel mode clears that colour everywhere, including holes. The result updates on a checkerboard and downloads as PNG.

Step-by-Step Usage Guide

  1. Drop an image with a plain or green-screen background.
  2. Check the detected key colour and raise Tolerance until the background clears.
  3. Add Edge softness to smooth the outline.
  4. Click the preview to add fill points in areas the corners do not reach.
  5. Download the transparent PNG.

Technical Specifications & Standards

Each pixel's distance from the key colour is measured as straight-line distance in RGB, and tolerance is a percentage of the largest possible distance. Pixels within tolerance become fully transparent. Pixels in the band just beyond it, set by edge softness, get partial transparency that rises with distance, which smooths the anti-aliased edges most images have. Connected mode is a flood fill: starting from the corners or your clicked points, it spreads to the four neighbours of each pixel within tolerance and stops at anything else. So white inside a white T-shirt survives as long as it does not touch the background. Softened edge pixels are changed but do not spread the fill, so it cannot leak through a soft boundary. Images are processed at up to 12 megapixels, with changes debounced so dragging a slider stays responsive. Photos with detailed, multicoloured backgrounds need a machine-learning model; this tool deliberately does not pretend to be one.

Targeted Use Cases

  • Cutting out a product photographed on a white sweep for an online shop.
  • Making a transparent PNG of a logo that was saved with a white box.
  • Lifting a handwritten signature off a scanned page for documents.
  • Removing a green screen behind a person shot for a thumbnail.

Notes & Gotchas

  • Start with low tolerance and raise it slowly; high values eat into the subject.
  • Use Connected mode when the subject contains the background colour.
  • Add a little edge softness for photos, and keep it at zero for pixel art and logos.
  • Shoot or scan on an evenly lit background for the cleanest results.

Frequently Asked Questions

Is this an AI background remover?

No. It removes pixels close to a chosen colour, which works well for plain or green-screen backgrounds. Photos of people in front of detailed scenes need a machine-learning model, which this tool does not use.

Why did part of my subject disappear?

Those pixels are close to the background colour and connected to it. Lower the tolerance, or switch to Connected mode if you used Every matching pixel. Edge softness can also be reduced.

Why are there bits of background left inside the subject?

In Connected mode the fill only spreads from the edges and the points you click. Click inside each enclosed gap to add a fill point, or use Every matching pixel mode.

What format is the result?

A PNG with an alpha channel, since PNG keeps transparency and every app supports it. The image never leaves your browser while it is processed.

Related tools

  • Universal Image Studio - Convert between PNG, JPG, WebP, and GIF. Resize, compress, and download — fully offline.
  • Image Cropper - Crop any image by dragging a selection, with rotate and flip controls. Export production-ready PNG or JPEG.
  • Image Converter (PNG, JPG, WebP, AVIF, BMP, ICO, GIF) - Batch convert images between PNG, JPG, WebP, AVIF, BMP, ICO and GIF in your browser. Set quality, pick a background for transparent areas, keep file names and download everything as one ZIP.
  • Screenshot Eyedropper & Palette Picker - Sample colors from app screenshots click-by-click, or pick anywhere with the system eyedropper (Chromium). Export Compose, Flutter, SwiftUI, HEX, and RGB.
  • Image Resizer - Resize images to exact pixel dimensions with aspect-ratio lock, and convert between PNG, JPEG, and WebP in one step.
  • Image to PDF - Combine JPG and PNG images into a single PDF with page size, orientation, and margin controls. Fully offline.