Three styles and when to use each
Grayscale is the classic black and white photo. Colors are converted to brightness values, giving a full range of grays. It suits portraits, street photography, architecture and anything where shape, texture and light matter more than color. It also hides distracting colors, mixed lighting and color casts.
High contrast reduces the picture to just two tones. It is less a photo effect and more a cleanup tool: scanned pages, receipts, handwritten notes, signatures, line art and logos come out crisp. It is also a fun graphic look for posters and stencils.
Sepia adds a warm brown tint over the grayscale image, imitating old prints. Use it for vintage, nostalgic or wedding-style pictures.
Getting a good black and white photo
Not every color photo converts well. A few things help:
- Strong light and shadow. Side light, window light and late afternoon sun give depth that grayscale shows off.
- Contrast between subjects. A red flower on green leaves can turn into two similar grays because both colors have about the same brightness. If your subject disappears, pick a different photo or try high contrast.
- Texture. Wood grain, wrinkles, clouds and stone all look richer without color.
- Busy or ugly colors. Clashing clothes or orange street lights stop being a problem once color is gone.
Grayscale uses a standard weighting that matches how human eyes perceive brightness, with green counting more than red and blue counting least. That is why a bright blue sky often looks darker than you expect.
Using the threshold slider
High-contrast mode needs one decision: where to draw the line between black and white. The slider controls that cutoff.
| Goal | Threshold tip |
|---|---|
| Clean up a scanned document | Raise it until text is solid, then back off if letters thicken |
| Remove a gray paper background | Lower it until the paper turns pure white |
| Bold poster or stencil look | Set it near the middle and check faces stay readable |
| Faint pencil drawing | Raise it so light strokes stay black |
Watch fine details like thin lines and small text while you adjust. Too low and they vanish into white; too high and the shadows fill in.
Formats and quality
The download keeps the format of your original file, and transparency is preserved for PNG and WebP. A high-contrast PNG of a document is often much smaller than the color original because it holds only two colors. Images can be up to 8,000 pixels per side.
Your original file is never modified. If you might want the color version later, simply keep it alongside the new black and white copy.