A wallpaper described as "true black", "pure black", or "OLED black" is very often #121212, #0A0A0A, or some other dark grey. At a glance, on a thumbnail, against a bright background, you cannot tell. On an OLED panel the difference is the entire point: #000000 switches pixels off, and anything above it does not.
Checking takes about a minute. Here is how, on every platform.
What you are actually checking for
You want the darkest region of the image to read exactly 0, 0, 0 in RGB, or #000000 in hex. Not close. Not 10, 10, 10. Zero.
There is no partial credit here. A pixel at #010101 is a pixel that is on.
Checking on iPhone
- Set the wallpaper, then take a screenshot of the home screen.
- Open the screenshot in the Photos app and tap Edit.
- There is no built-in colour picker, so use any free one from the App Store, or send the screenshot to a desktop.
Faster alternative: open the wallpaper image itself in the Files app, screenshot it, and use the Markup eyedropper. It shows you the colour it sampled, though not the hex value, so this is a rough check rather than a definitive one.
For a definitive answer on iPhone, the desktop method below is more reliable.
Checking on Android
Android makes this easier because most gallery apps and many file managers expose image details directly.
- Open the wallpaper in Google Photos.
- Use any free colour-picker app, or Google Lens, pointed at the darkest area.
Samsung devices with the built-in Colour Picker in the Edit tools can sample a pixel and show the hex directly.
Checking on Windows
This is the most reliable method and takes seconds:
- Open the wallpaper file in Paint.
- Select the eyedropper (Colour picker) tool and click the darkest part of the image.
- Open Edit colours. The Red, Green and Blue boxes show the exact value.
All three must read 0.
Checking on Mac
macOS ships with Digital Colour Meter, which most people never open:
- Open Digital Colour Meter from Applications → Utilities.
- Set the display mode to Display native values.
- Hover over the darkest region of the wallpaper.
It reads out R, G and B live as you move. Again, you want three zeroes.
Sample several spots, not one. Plenty of wallpapers have a genuinely black corner and a dark grey gradient across the rest, which passes a single-pixel check while failing everywhere it matters.
Checking in the browser, with no software at all
If the wallpaper is already open in a browser tab:
- Right-click the image and choose Inspect.
- In the DevTools Console, there is no one-liner for this, so the simplest route is a screenshot plus one of the methods above.
Most operating systems' built-in screenshot tools now include a magnifier that shows the pixel colour while you drag. On Windows, Win + Shift + S with the magnifier; on Mac, Cmd + Shift + 4 shows RGB values under the cursor in recent versions.
What counts as close enough?
Nothing, if the goal is battery or burn-in. A pixel is either off or it is not.
It is still worth knowing the scale of what you are looking at:
| Value | Hex | On an OLED |
|---|---|---|
| 0, 0, 0 | #000000 |
Pixel off, zero draw |
| 10, 10, 10 | #0A0A0A |
On, very dim |
| 18, 18, 18 | #121212 |
On - Material Design's dark surface |
| 26, 26, 26 | #1A1A1A |
On, visibly grey beside true black |
Put pure black next to #121212 on an OLED screen in a dark room and the difference is obvious - one is a hole in the display, the other is grey. In daylight, or in a thumbnail, they look the same. That is exactly why so many wallpapers get away with it.
Why pure black is wrong for apps but right for wallpapers
There is a real reason interface designers avoid pure black, and it is worth understanding so you know when the advice does not apply to you.
In an interface, pure black behind white text creates harsh contrast that tires the eyes, and on some OLED panels it causes visible smearing as pixels switch fully off and on while you scroll. #121212 avoids both.
A wallpaper has neither problem. It is static, and it is not sitting behind body text you read for an hour. The reasoning that makes #121212 correct for an app background does not transfer - but the number does, which is how it ends up in wallpaper packs.
Checking before you download
Rather than downloading and then testing, you can often check first:
- Open the preview at full size rather than judging the thumbnail. Thumbnails are re-compressed and lighter than the original almost every time.
- Look for a stated format. If a listing does not say PNG, assume JPEG, and assume it is not pure black.
- Be sceptical of photographic-looking black images. A photograph of a dark scene essentially never contains pure black; there is always sensor noise.
Why compression ruins this
One trap worth knowing: a JPEG of a true black wallpaper is often not true black any more.
JPEG compression works in blocks and introduces small variations around edges. A #000000 background saved as JPEG can come back as a field of values hovering between 0 and 4, especially near any bright detail. It still looks black. It no longer switches pixels off.
If you care about this, the wallpaper needs to be a PNG. Every download on PattrnLab is a PNG for exactly this reason.
Why so many "OLED wallpapers" fail the test
It is rarely deliberate. Three common causes:
- The source was a photo or a render with a near-black background rather than a generated flat black.
- It was saved as JPEG somewhere in the chain, as above.
- A "dark" palette was used instead of a black one. Material Design's recommended dark surface is
#121212, and a lot of wallpaper packs inherit that number without thinking about OLED at all.
That last one is worth sitting with: #121212 is an excellent choice for an app's background, because pure black next to text can look harsh and cause smearing while scrolling. It is the wrong choice for a wallpaper whose whole purpose is switching pixels off.
Wallpapers that pass the test by construction
Rather than checking afterwards, you can start from something generated black. Every wallpaper in the true black OLED collection is rendered with a literal #000000 background and downloaded as a PNG, so it survives the round trip to your device intact.
Check one yourself with any method above. That is rather the point.
FAQ
How to check if a wallpaper is true black
Open it in any colour picker and sample the darkest area. Paint on Windows and Digital Colour Meter on macOS both show exact RGB values. You want 0, 0, 0 - anything higher is a pixel that is still on.
Is #121212 true black?
No. #121212 is RGB 18, 18, 18 - a dark grey, and the dark surface colour Material Design recommends for app backgrounds. It looks black in a thumbnail and behaves nothing like black on an OLED panel, where only #000000 switches pixels off.
Why is my black wallpaper not pure black?
Usually JPEG compression. Saving a #000000 image as JPEG introduces small variations around edges, so the background comes back as values hovering between 0 and 4. It still looks black and no longer switches pixels off. A true black wallpaper has to be a PNG.
What is the hex code for true black?
#000000, which is RGB 0, 0, 0 - the absence of all three colour channels. Any other value, however close, is a colour rather than an absence of one.