Convert an image to grayscale or pure black and white.
Keep a full range of gray tones or reduce the image to two tones. Tune brightness, contrast, threshold, and inversion, then verify the preview and download a local PNG.
Local processing. Canvas edits and previews happen on this device; the selected image is not sent to imgrove. Privacy details
How to use Black & White Image
- Drop one JPG, PNG, or WebP image and choose grayscale or pure black-and-white output.
- Tune brightness and contrast; in two-tone mode, move the 0–255 threshold and check the reported black-pixel share.
- Invert only when the destination needs light marks on a dark field, then download the PNG and inspect thin lines, shadows, and transparency.
How it works
- The browser decodes one JPG, PNG, or WebP, calculates a Rec.709-style luma score from each visible RGB pixel, and keeps the original alpha value.
- Brightness shifts that score, contrast spreads or compresses it around 128, and pure black-and-white mode maps values below the chosen threshold to 0 and values at or above it to 255.
- A monotonic render version binds every preview and PNG to the current File and complete settings, so a slower old adjustment cannot replace a newer result.
Formats and limits
| Input | One JPG, PNG, or WebP image. |
|---|---|
| Grayscale mode | Equal RGB channel values retain intermediate tones from 0 through 255. |
| Pure black and white mode | Every visible RGB pixel becomes 0 or 255; no dithering pattern is added. |
| Controls | Brightness -100 to +100, contrast -100 to +100, threshold 0 to 255, and optional inversion. |
| Output | One static PNG at the source pixel dimensions, with a preview and measured tone or black-pixel summary. |
| Privacy | Decoding, pixel conversion, measurement, preview, and PNG encoding happen in this browser tab. |
| Metadata | Canvas creates a new PNG; source EXIF, IPTC, XMP, animation, and container-specific data are not copied. |
Real failure cases
- A threshold that is too high can fill shadows and paper texture; one that is too low can erase pale or thin marks.
- The browser transform is not a color-managed CMYK or print-proofing workflow.
- Very large source dimensions can exceed browser Canvas memory, and the filter cannot add detail to a soft or low-resolution image.
Example result to verify
| Original | 1200x800 JPG scan with a pale signature on light paper. |
|---|---|
| Settings | Pure black and white, brightness 0, contrast +25, threshold 155, inversion off. |
| Output | 1200x800 PNG with only black and white visible RGB values plus the reported black-pixel share. |
| Verify | Inspect the signature at final size and lower the threshold if paper texture fills in, or raise it if pale strokes disappear. |
Best for
- Keeping facial tone, texture, gradients, and shadows in grayscale.
- Making two-tone signatures, forms, masks, stencils, and line art.
- Measuring how a threshold changes the black-pixel share.
What you get
- A PNG at the original pixel dimensions with equal RGB values for grayscale or pure 0/255 black-and-white pixels.
- A live preview with mode, threshold or tone range, black-pixel share, brightness, contrast, inversion, and output dimensions.
Before you download
- The Rec.709-style browser transform is not a color-managed print-proofing conversion.
- Canvas creates a new static PNG, so source metadata, animation, and container-specific data are not copied.
- A harsh threshold can erase thin marks or fill shadows, so inspect the downloaded result at its real size.
Common examples
Use this converter when the real decision is whether the image should keep intermediate gray tones or contain only pure black and white pixels.
- Portrait or product photo. Start with grayscale so faces, fabric, reflections, and shadows keep their tonal shape. Use small brightness and contrast moves.
- Signature or scanned form. Choose pure black and white, start at threshold 128, then raise the cutoff for more black area or lower it for more white area.
- Stencil, mask, or line art. Use two-tone mode when every visible pixel must join the black or white region. Check thin strokes at the final display or print size.
- Light marks on a dark field. Finish the tone and threshold settings first, then enable Invert to swap the rendered black and white values.
Helpful next tools
- Grayscale vs Black and White Guide - use the three-question decision rule and a worked 0–255 threshold example.
- Image to Coloring Page - trace local edges when a threshold silhouette is not the line drawing you need.
- Image Size Checker - verify the downloaded PNG dimensions, file size, transparency, and DPI.
- PNG Format Guide - understand the lossless PNG output and alpha support.
Questions about Black & White Image
What is the difference between grayscale and pure black and white?
Grayscale keeps intermediate tones between black and white. Pure black-and-white mode maps every visible pixel to black or white with the selected threshold.
What does the threshold control do?
Pixels below the 0–255 cutoff become black, while pixels at or above it become white. Raising the threshold creates more black area; lowering it creates more white area.
Which mode should I use for a photo?
Start with grayscale for portraits, products, texture, clouds, and shadows. Use pure black and white for forms, signatures, stencils, masks, and line art that need two clear regions.
Does the converter preserve transparency?
It leaves the browser-decoded alpha value unchanged and exports PNG. Always inspect the downloaded result because browser decoding and source formats can vary.
Does conversion keep EXIF metadata or animation?
No. Canvas creates a new static PNG from decoded pixels, so source EXIF, IPTC, XMP, animation, and container-specific data are not copied. Keep the original file.