#00FF00, which CSS names lime. Only the green sub-pixels are lit, and they carry most of a display's brightness: about 72 percent of what full white gives, more than red and blue put together.
The page's own dimmer, not your device's brightness.
This green screen test fills your display with pure green, #00FF00, in one press. Use it as a small backdrop to key out, or to check the screen itself: on green, a faulty sub-pixel shows as a dot.
Read the full guide
Green screen testing, step by step
1. Press Go full screen for a full green screen, and prop the device behind the object.
2. Film or photograph it from the front.
3. Apply the key in your editing program. Patches that stay behind are shadows or reflections: turn the screen and try again.
All green screen colors on this page
Pure green lights the green sub-pixels alone. The other seven are named CSS greens, from light green to dark green, each with its hex code and its share of white's light. Copy hex copies the code on show, ready to use as a green screen color background in an editing program.
Lower Dimmer when green light tints the edges of the object in front.
A phone works as a backdrop only for things smaller than its screen.
Questions and answers
How do I test a green screen?
Fill the screen with pure green, record it, and apply the key in your editing program. Patches that do not vanish are places the camera saw as a different green: often a shadow, a reflection or uneven brightness.
How do I make a bright green screen full screen?
Keep pure green, #00FF00, press Go full screen and turn up the device's own brightness: Dimmer here only darkens the shade. After three seconds the bar fades, and what is left is a blank green screen from edge to edge.
Why are green screens green?
Green is far from skin tones, green clothing is less common than blue, and cameras are more sensitive to green light, so green gives a clean key. A blue backdrop is used when the subject itself is green, such as a plant.
Can a phone or monitor work as a green screen?
For a small subject, yes. The display is an evenly lit green field, but it covers only what fits in front of it, and a glossy screen can mirror room lights, which may not key out.
What does a dot on a green screen mean?
On pure green, a black dot is a green sub-pixel that stays off, a yellow dot is a red one stuck on and a cyan dot is a blue one stuck on. The dead pixel test confirms it on six colors.
All 18 shades and uses
Greens, from pure green to dark green 8
Pure green#00FF00, which CSS names lime. Only the green sub-pixels are lit, and they carry most of a display's brightness: about 72 percent of what full white gives, more than red and blue put together.
Spring green#00FF7F: green at full with blue at half. A cooler, mintier green that gives about 73 percent of white's light, a little more than pure green because the blue adds to it.
Light green#90EE90: a pale green with red and blue both lit, at about 69 percent of white's light. It tints gently, so it suits a soft wash more than a backdrop.
Lime green#32CD32: a leafy green one step down from pure green, at about 45 percent of white's light. A little red and blue are mixed in, so it looks less electric on a bright screen.
Sea green#2E8B57: a muted blue-green at about 20 percent of white's light. All three sub-pixels are lit at different levels, so it is a color for a backdrop or a wash, not for naming a faulty sub-pixel.
Show all 18 shades and uses (13 more)
Greens, from pure green to dark green, continued
Forest green#228B22: a deep green at about 19 percent of white's light. Dark enough to sit quietly behind a bright object, and still plainly green on a dim screen.
Half-strength green#008000, the color CSS names green: the green sub-pixels alone at level 128 of 255. Half the signal gives only about 15 percent of white's light, because screens do not brighten in a straight line.
Dark green#006400: green alone at level 100 of 255, about 9.1 percent of white's light, the darkest shade here. Use it where pure green would light up the whole room.
As a green backdrop 8
A small green screen behind a productStand a phone or tablet upright behind a small object and film from the front. The lit screen is one even green with no creases and no shadows of its own. It covers only what fits in front of the display.
A green field to replace in a video editRecord this window on a computer and the green area becomes a block that an editing program can swap for a picture or a title. Once the controls fade, the field is one flat color, which is what a key matches on.
Why the key color is usually greenGreen and blue are the colors furthest from skin tones. Green won out in television because fewer clothes are green than blue, and because cameras are more sensitive to green light, which gives a cleaner key.
Green light spilling onto the subjectLight from a green backdrop lands on whatever stands near it and tints its edges green. This is called spill. A screen is a light source, so move the object forward or lower Dimmer until the green edge fades.
Reflections and shadows that will not keyA glossy screen mirrors lamps and windows as pale shapes, and a camera reads them as a different green. Shiny or shadowed areas may not register for replacement. Turn the screen or the lamp until the green looks even from the camera.
One narrow range of green for the keyA key works best when the backdrop is as narrow a range of color as possible. A display seen at an angle can look darker toward one side, so point the camera square at the screen and check the green from its position.
A backdrop too dim or too bright in the cameraUnder-exposed or over-exposed, a colored backdrop loses saturation and keys poorly. Raise the device's brightness until the camera shows a bright, saturated green, then set the exposure for the object in front.
Copying a green as a hex codeEach shade prints its hex code under the field, and Copy hex puts it on the clipboard. Paste it as the key color in an editing program so the key starts on the exact value this page shows.
Checking the screen on green 2
Green sub-pixel off: a black speckOn pure green only the green sub-pixels are lit, so one that stays off leaves a black point. On a white screen the same fault looks magenta, because red and blue still shine there.
A yellow or cyan point on greenA red sub-pixel stuck on adds red light to the green and shows as yellow. A blue one stuck on shows as cyan, and both together as white. The dead pixel test steps through six colors to confirm which it is.
How this list was compiled: Shades, checks and uses chosen and written for this page. Every hex value is a CSS named color, taken from the table of named colors at https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values/named-color, read 2026-10-02. The share of light printed for each shade is its relative luminance (0.2126 R + 0.7152 G + 0.0722 B on linear values, pure white as 100), worked out from the formulas at https://en.wikipedia.org/wiki/SRGB, read 2026-10-02. That a pixel is made of three sub-pixels, that a dark dot is one that stays off and a stuck sub-pixel one that stays lit, is from https://en.wikipedia.org/wiki/Defective_pixel; that red and green light make yellow, red and blue magenta, green and blue cyan, and all three white, is from https://en.wikipedia.org/wiki/RGB_color_model; both read 2026-10-02. Why a key color is usually green or blue (the colors furthest from skin tone, green clothing being less common than blue, cameras being more sensitive to green), spill, shadows that may not register for replacement, shiny surfaces that reflect the lights, and a blue screen for a subject that is mostly green, are from https://en.wikipedia.org/wiki/Chroma_key, read 2026-10-02. A color on a screen is not a match for paint, print or another screen, and nothing here is a measurement. Licence: own work