Brighten a dark photo or fix flat contrast with live sliders, then download the adjusted image at full resolution.
Pixels are adjusted in this tab. Nothing is uploaded.
Choose an image to begin.
A live preview appears here as you move the sliders.
Brightness and contrast are applied to the colour channels only; alpha is copied unchanged. JPEG output flattens transparency onto black, so choose PNG if the image has transparent areas.
Your file is never sent to a server. It is read and processed by your own browser, and the results are not stored.
Brightness adds a constant to each colour channel. Contrast scales each channel away from the midpoint. The tool builds a 256-entry lookup table from those two values and applies it once per pixel, which is why the preview can update on every slider movement.
A lookup table is exact for these operations and avoids per-pixel floating-point work. It also makes the result deterministic: the same slider values produce the same bytes every time.
Fix exposure first, then contrast. Raising contrast before brightness can clip highlights that a gentler exposure change would have preserved. Stop before the brightest areas lose texture; a slightly flat image is easier to use than a clipped one.
For anything beyond a global tone change — selective edits, colour grading, shadow recovery — a full editor is the right tool. This page is deliberately a two-slider adjustment, not a replacement for one.
No. Adjust Photo Brightness & Contrast runs in your browser, and the file is read there rather than sent to a server for processing. Our host still sees ordinary page-request metadata, which is described on the privacy page.
Yes, Adjust Photo Brightness & Contrast is free, with no paid tier, no account, and no watermark added to your output. The limits are technical rather than commercial: file size, page count and supported formats are listed on this page.
Adjust Photo Brightness & Contrast supports .jpg, .jpeg, .png, .webp files up to 25MB directly in your browser.
The same tone curve is applied in both cases. The preview is drawn at a reduced size so dragging a slider stays responsive, while the download is produced from the full-resolution source with the same brightness and contrast values.
Partly. Lifting brightness reveals detail that is already recorded, but it also amplifies noise and can clip highlights. If the shadows are crushed to pure black, no slider can invent the missing data. The tool does not claim otherwise.
Brightness shifts every colour channel by the same amount, from −100 to +100. Contrast pushes values away from the midpoint. Both are applied to colour only; the alpha channel is copied unchanged.