Free · runs in your browser
Work out whether it’s your screen or the video itself, then fix it: six quick checks for viewers, and what to do if it’s your own upload that came out too dark.
A YouTube video usually looks dark for one of two reasons: something on your device is dimming it (auto-brightness, a battery saver, an HDR or picture-mode setting, or the browser’s graphics path), or the video itself was uploaded too dark. To tell which, open the same video on another device. If it looks fine there, the fix is a setting on your side; if it’s dark everywhere, the file is the problem and only a brighter upload will change it.
If you are the creator, the second case is the common one: footage that looked acceptable on a bright phone screen turns out to be murky on everyone else’s, or an export lost brightness on the way. The seven fixes below go from quickest to most involved, and the last one is how to brighten your video before uploading it again.
YouTube can’t replace the file behind a published video, and its editor has no brightness control, so the fix is a brighter copy uploaded as a new video.
Use the video you exported or filmed, not a download from YouTube: a re-download has already been compressed once more.
Open it in the tool on this page with Select video and press Auto brighten. Check with Before and after, and adjust Strength if it’s too much or too little.
Under Export settings, leave Size at the original and set Quality to High, then select Export video and Download video.
Upload the new file to YouTube, check it on a phone and a computer, then set the old version to Private or Unlisted and update any links, playlists or end screens that point to it.
Phones lower the screen automatically in dim surroundings, and some also cut brightness when they warm up or when the battery is low. The YouTube app follows the system brightness, so a video watched in bed at night is shown on a screen running at a fraction of its daytime brightness. Swipe the brightness up in Control Centre on iPhone or the quick settings panel on Android and the same video usually looks normal.
iPhone users sometimes notice the opposite with their own clips: a video looks bright and punchy in the Photos app and duller on YouTube. Recent iPhones record HDR (Dolby Vision) by default, and the Photos app shows it at the screen’s HDR brightness. Once uploaded, viewers on standard screens see YouTube’s SDR version, which can’t reach those highlights, so the whole picture appears dimmer.
The most common reason is the simplest: the footage was underexposed, and the bright phone screen you edited on hid it. Look at the original on a computer monitor at normal brightness. If it’s murky there too, brighten it before uploading. The guide to fixing a video that is too dark explains why cameras underexpose in dim light.
When you upload HDR video, YouTube keeps an HDR version for HDR screens and makes a standard version for everyone else. If the file’s HDR information was lost or changed during editing, or the edit mixed HDR and SDR clips, the standard version can come out dim, grey or oddly contrasty. Exporting a plain SDR MP4 before uploading avoids the conversion altogether. Opening the clip in the tool here and exporting it gives you an 8-bit SDR file, and you can brighten it at the same time; see brightening iPhone video for HDR clips straight from the phone.
Video is normally stored in “limited range”, where black is level 16 and white 235, not 0 and 255. If an editor exports full range but labels it as limited (or the other way round), players stretch or squeeze the levels: the result looks crushed and too dark, or grey and washed out. Leave range settings at their defaults unless you know you need otherwise.
Editing on a Mac adds another twist: QuickTime-based previews on macOS can display Rec. 709 video a little lighter than browsers and most other players do, so an edit that looked right in the editor can look darker and more contrasty once it’s on YouTube. Judge brightness in a browser, or on a second device, before you export the final version.
Open the original file in the tool at the top of this page and press Auto brighten. It measures the clip, lifts exposure and shadows to a natural level, holds back bright skies and lamps, and adds a little Noise reduction for the grain that dark footage carries. For specific problems use Night video, Dim room, Backlit or Slightly dark, and compare the result with Before and after.
Usually the phone’s screen: auto-brightness or a battery saver has dimmed it. If it’s your own HDR iPhone clip, the Photos app shows it at HDR brightness, while YouTube shows many viewers a standard version that looks dimmer.
The common causes are HDR footage converted to a standard version, a levels mismatch between limited and full range in the export, or comparing against a brighter preview on a Mac or an HDR phone. If the original itself is dim on a normal monitor, brighten the file and upload it again.
A screen that dims during playback is usually adaptive brightness reacting to the room, a power-saving mode, or a TV’s light sensor or energy-saving setting. Turn those off to check. Ambient mode only adds a glow around the player; it doesn’t dim the video.
Open the gear menu in the YouTube player and switch Ambient mode off. In the phone app it sits in the same player settings, sometimes under Additional settings, depending on the app version.
Not in place. YouTube Studio’s editor can trim and blur, but it has no brightness adjustment, and a published video’s file can’t be swapped. Brighten the original and upload it as a new video.
On an HDR screen, HDR videos look brighter in the highlights. On a standard screen you see YouTube’s converted version, which can look slightly dimmer or flatter, particularly if the HDR information was handled badly in editing.
Brightening re-encodes the video, so export at the original size with Quality set to High. That gives YouTube plenty of detail to work with before it compresses the upload itself.