Light, not grey
Exposure works in linear light, like opening up a lens, so colours stay rich and lamps roll off softly instead of turning into white blobs.
Free · runs in your browser
Brighten video online
Fix a video that came out too dark. Auto brighten measures the light in your clip and lifts it to a natural level, with exposure, shadows and noise reduction on hand when you want more control. Nothing is uploaded.
Why brighten your video here
Grain under control
Lifting shadows reveals noise. Noise reduction smooths the speckles in the dark areas you brighten and leaves detail elsewhere alone.
Private and free
The video is graded on your own device and never uploaded. No account, no watermark and no length limit.
How it works
How to brighten a dark video
Open the dark video
Drop it on the page or choose Select video. MP4, MOV, WebM and MKV all open, including footage from iPhone and Android phones.
(enlarge image) Drop the clip on the card, or press Select video (Ctrl+O).
- Select video
Press Auto brighten or pick a quick fix
Auto brighten measures the light in your clip and lifts it to a natural level. Night video, Dim room, Backlit and Slightly dark suit common problems, and Strength sets how far to go. Turn on Before and after to compare.
(enlarge image) Press Auto brighten, then switch on Before and after and drag the divider to compare. Strength sets how far it goes.
- Auto brighten (A)
- Strength
- Drag to compare
- Export video
Export and download
Choose Export video, wait for the progress bar, then Download video. On a phone, Share sends it to Photos or another app.
(enlarge image) When Your video is ready appears, choose Download video, or Share on a phone.
- Download video
- Adjust again
The science
What actually happens when you brighten a video
A camera stores light in a compressed, gamma-encoded form: the numbers in the file are not proportional to the light that hit the sensor. Mid grey, which reflects 18% of the light, is stored at roughly 46% of full scale, and the darkest tenth of the scene is squeezed into a small band of codes. That is why “brighter” can mean several different maths operations, and why they look so different.
- Exposure +1 EV
- Brightness +60
- Midtones (gamma) +60
- Unchanged
| Input | Exposure +1 EV | Brightness +60 | Midtones (gamma) +60 |
|---|---|---|---|
| 10% | 14% | 14% | 20% |
| 25% | 35% | 34% | 40% |
| 50% | 69% | 61% | 64% |
| 75% | 92% | 82% | 83% |
Exposure, brightness and gamma are not the same
Exposure converts the picture back to linear light, multiplies it, and encodes it again. One stop doubles the light, exactly as opening the aperture by a stop would. Because every pixel is scaled by the same factor, contrast between a face and the wall behind it stays believable, and colours keep their hue. The catch is the top end: values that were already bright get pushed past white. brighten.video bends those into white along a smooth shoulder rather than cutting them off, so lamps and skies keep some shape.
Brightness, in most editors, adds or scales the stored numbers directly. It moves dark and mid tones up by similar amounts, which is quick but can make blacks look grey. On a TV, the setting called Brightness actually sets the black level. Gamma (Midtones) bends the curve between fixed black and white points; it lifts the darker midtones most and leaves the extremes untouched, which is often the most flattering fix for faces in a dim room.
Why lifted shadows look noisy
A dark clip is mostly made of small numbers, and small numbers are where sensor noise and compression damage live. In a phone video shot at night, the shadows may span only twenty or thirty of the 256 levels an 8-bit file can hold. Multiply them by four and the gaps between levels show as banding, while random speckles that were invisible become obvious, especially as blotches of colour. Noise reduction here smooths those areas while respecting edges, and works hardest on colour noise, which the eye finds most ugly.
Clipping: what can’t be brought back
Pixels recorded as pure black (or pure white) carry no detail at all, and no software can invent it. The Histogram under More options shows where your clip sits: a tall spike against the left edge means crushed shadows, one against the right means blown highlights. Aim to brighten until the middle of the histogram moves right while both edges stay clear.
Codecs, bit depth and quality
Brightening changes every pixel, so the video has to be decoded and encoded again; no tool can brighten a video losslessly. Phone footage is usually 8-bit H.264 or HEVC, and some iPhone clips are 10-bit HDR, which your browser converts for display. The export is 8-bit H.264 in an MP4 (or WebM where the browser supports it) at a generous bitrate, because lifted shadows contain fine texture that a stingy encoder would turn into blocks.
Guides
Fixes for every kind of dark footage
- Fix a video that is too dark Why clips come out dark, and the quickest way to rescue one.
- Fix underexposed footage with exposure in stops Exposure, shadows and scopes for footage shot a stop or two under.
- Enhance a night or low-light video Brighten after-dark footage while keeping it looking like night.
- Brighten a backlit subject in a video Rescue a person filmed in front of a window, sunset or bright sky.
- Brighten a video without losing quality Bitrate, bit depth, banding and noise: keeping a brightened clip clean.
Brightening in the apps you already have
- How to brighten a video on iPhone Use Exposure, Brilliance and Shadows in the Photos app, and revert to the original at any time.
- How to brighten a video on Android Lift a dark clip with Google Photos’ Adjust tools or the Tone panel in Samsung Gallery.
- How to brighten a video on Windows Use Clipchamp’s Adjust colors tab on Windows 11, or a browser tool that keeps the file on your PC.
- How to brighten a video on a Mac Use the Light slider in Photos or Color Correction in iMovie, and export a brighter copy.
- How to brighten a video in Premiere Pro Lumetri Basic Correction, the Luma waveform and export settings for dark footage.
- How to brighten a video in CapCut Use Adjust in the CapCut app or desktop editor to lift Brightness, Exposure and Shadows.
- How to brighten a video in DaVinci Resolve Primaries wheels, HDR palette Exposure, scopes and Deliver settings for dark clips.
- How to brighten a video in VLC Brighten playback with Image adjust, then save a copy with the Image properties filter.
Questions about brightening video
The tool runs on your own device, so the answers below are about light, noise and file formats rather than uploads and accounts.
How do I make a dark video brighter?
Open the video above and press Auto brighten. It measures how dark the footage is and lifts exposure and shadows to a natural level. If the result is too strong or too weak, drag Strength, then select Export video and download the file.
Is my video uploaded anywhere?
No. brighten.video decodes, grades and re-encodes the file inside your browser using WebCodecs and your device’s graphics chip. Nothing about the picture or the sound is sent to a server.
What is the difference between exposure, brightness and gamma?
Exposure multiplies the light in every pixel, the way a wider aperture or slower shutter would, so it keeps the ratios between dark and bright areas. Brightness shifts the picture up or down evenly. Gamma (Midtones) bends the middle of the tonal range while pure black and pure white stay where they are. For underexposed footage, exposure usually looks the most natural.
Why does my video look grainy after brightening it?
Dark footage already contains sensor noise and compression blocks; they were just too dark to see. Lifting the shadows makes them visible. Open More options and raise Noise reduction, or lower Strength, and move Blacks a little to the left so the darkest areas go cleanly black.
Can I brighten a night video without it looking fake?
Yes. The Night video fix aims for a lifted but still night-time look: it brightens the street and faces, holds back street lights with Highlights, keeps the sky dark with Blacks and adds Noise reduction. Use the Before and after split to judge it.
My subject is a dark silhouette in front of a window. Can that be fixed?
Choose Backlit. It lifts the shadows hard and pulls the bright background down so the person and the window both keep detail. Truly black areas carry no information, so a full silhouette can only be lightened so far.
Will brightening reduce the quality?
Every frame has to be redrawn, so the video is re-encoded rather than copied. It is encoded at a generous bitrate, and you can choose High under Export settings for the closest match. What really limits quality is the original: an 8-bit phone clip only has so much information in its shadows.
Does it keep the sound?
Yes. The audio track is kept and stays in sync. Turn off Keep sound under Export settings if you want a silent file.
Can I fine-tune the result myself?
Open More options for Exposure, Brightness, Midtones (gamma), Contrast, Shadows, Highlights, Blacks, Whites, Saturation, Vibrance and Noise reduction. Each has an exact number field and its own reset, and the Histogram and Waveform show where the tones sit.
How do I compare the original with the brightened version?
Turn on Before and after, or press B. The preview splits: the original on the left, the result on the right. Drag the divider, or focus it and use the arrow keys.
Can I brighten only part of the video?
You can trim the clip with the scissors button under the preview, or with I and O at the playhead, and only the part you keep is exported. The same settings apply to the whole kept section.
Which formats and sizes work?
MP4, MOV, WebM and MKV open in modern browsers, including HEVC files where the browser can decode them; unusual codecs fall back to a converter that runs on your device. You can save as MP4 or, where supported, WebM, at the original size or smaller.
Does it work on a phone?
Yes. It runs in up-to-date Safari, Chrome, Edge and Firefox, on phones and tablets as well as computers. Long 4K clips take longer on a phone because every frame is processed on the device.