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Brighten Video Online — Fix Dark Videos, Free, No Upload

Brighten video online: lift a dark clip, add contrast, adjust colour or go black and white. Runs in your browser. No upload, no watermark, no signup.

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Drop a file here or click to browseMP4, MOV, WebM, MKV, AVI — any video your browser can read🔒 Processed on your device — never uploaded

Lifts or lowers every pixel by the same amount.

Spreads light and dark apart. Raise it a little when brightening a washed-out clip.

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Rescue a video that came out too dark

Video filmed indoors, at dusk or against a window often comes out too dark or too flat. This tool lifts the brightness, adds contrast and adjusts the colour in one pass, so you can fix a clip without opening an editor. It runs on your own device and nothing is uploaded.

What the three settings do

Brightness adds the same amount of light to every pixel, so it lifts shadows and highlights together. Contrast pushes light and dark further apart, which brings back the punch that brightening alone washes out. Colour changes how strong the colours are, from black and white at zero to vivid at 1.5. Brighten a little, add a touch of contrast, and most clips look natural.

How much is enough

Small steps work best. A brightness of +0.1 or +0.2 with a contrast of 1.1 is a clear improvement for most dim clips, and +0.3 is for very dark footage. Bright areas can burn out to pure white and lose detail that cannot be brought back, so if a sky or a lamp starts to look flat, step the brightness down one notch.

What a filter cannot fix

A filter can lift what the camera recorded but cannot recover detail that was never captured. Pure black shadows stay black, and a very dark clip shows more grain once it is brightened. Shooting with more light is the real fix; this tool is the rescue for footage you already have.

After adjusting

Check the result, then shrink it for sharing with the video compressor or cut it to length with the video trimmer. If the clip is also the wrong way up, rotate it first.

Frequently asked questions

How do I make a dark video brighter?
Drop the video into the box, leave Brightness at +0.1 or raise it to +0.2, keep Contrast at 1.1 and press Apply to video. The tool makes a new MP4 with the adjustment applied, and you download it. Your original file is not changed.
What is the difference between brightness and contrast?
Brightness lifts or lowers every pixel by the same amount, so the whole picture gets lighter or darker. Contrast spreads the light and dark parts further apart, which makes the picture punchier. Brightening alone can look washed out, which a little contrast corrects.
Why does my video look grey and washed out after brightening?
Brightness lifts the blacks as well as everything else, so they turn dark grey. Raise the contrast one step, to 1.1 or 1.2, to push the darks back down, or lower the brightness a step.
Can I turn a video black and white?
Yes. Set Colour to Black and white and leave brightness and contrast at their defaults, or adjust them as well. Colour 1 leaves the colours as they were, and values above 1 make them richer.
Will this rescue a video that is almost completely black?
Only partly. A filter can lift what was recorded but cannot create detail that the camera never captured, and a very dark clip shows more grain when it is brightened. Use the highest brightness step and expect noise.
What do the numbers in the options mean?
Brightness runs from −0.2 (darker) to +0.3 (brighter) with 0 meaning no change. Contrast of 1 means no change, below 1 flattens the picture and above 1 strengthens it. Colour 0 is black and white, 1 is unchanged and 1.5 is vivid.
Does it change the sound, size or quality?
The picture is re-encoded once at a high quality setting and the sound is carried over as AAC. The resolution and the frame rate stay the same.
Is my video uploaded, and is it free?
Nothing is uploaded. The adjustment runs in your browser with a WebAssembly build of FFmpeg, and only the engine is downloaded the first time. It is free, with no watermark, no account and no limit on how many clips you adjust.

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