Fix the red pupils caused by a camera flash in seconds. Click on each eye or drag a box around both, and the tool finds the red pixels and turns them into a natural dark pupil while keeping the catch-light. Everything runs in your browser.
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Click on a red pupil to fix it.
Tip: zoom in on small faces. Each click is one step you can undo.
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How to use the Red Eye Remover
Open your photo: drop it on the box, paste it with Ctrl+V or press Choose photo. A sample portrait is loaded so you can try the tool first.
Click on each red eye, or drag a box around both eyes. Only red, pupil-like pixels inside the circle or box are corrected.
Try Auto-fix to search the whole photo for round red pupils at once, then undo anything you do not like.
Fine-tune: raise Sensitivity if some red is left, lower it if nearby skin changes; set Pupil darkness for a natural look. Zoom in for small faces.
Hold Compare to see the original, then press Download to save the fixed photo as JPG or PNG.
How the red eye correction works
A flash-lit pupil is red because the red channel is much stronger than green and blue. For every pixel inside your click or box the tool computes a redness ratio:
redness = R ÷ ((G + B) ÷ 2)
Normal skin has a ratio of roughly 1.2 to 1.5, while a red pupil is usually above 2.5. The Sensitivity slider sets the cut-off (from about 2.3 at the lowest setting down to 1.1 at the highest). Pixels above it are grouped into connected blobs, small stray specks are ignored, and the blob is grown by two pixels to catch the soft edge.
Each selected pixel then gets its red channel replaced by the average of green and blue, which turns the red into a neutral grey-black, and all three channels are darkened by the Pupil darkness amount. The bright white catch-light is not red, so it is kept and the eye still looks alive. Pixels near the threshold are only partly corrected, so the edge of the pupil blends smoothly into the iris.
Tips for natural-looking eyes
Click the center of the pupil with a brush slightly bigger than the red area. A very large brush is fine too: only red pixels are touched.
Group photos: zoom to 200% or 400%, or drag a box around each pair of eyes.
Orange or pink pupils (common with blue eyes and some phone flashes) need a higher Sensitivity, around 70 to 85.
Too black? Lower Pupil darkness to 20 to 35 % for light-colored eyes; dark brown eyes look best around 45 to 60 %.
Prevent red eye next time: turn on more room light so the pupils shrink, use the camera's red-eye reduction pre-flash, or bounce the flash off the ceiling.
Settings at a glance
Problem
What to change
Red ring left around the pupil
Raise Sensitivity by 10 and click again
Skin or eyelid turned grey
Undo, lower Sensitivity, use a smaller brush
Pupil looks flat or painted
Undo and lower Pupil darkness
Auto-fix missed an eye
Click on it manually, the detector only accepts round blobs
Auto-fix changed something else
Press Undo (Ctrl+Z) and fix the eyes by clicking
Frequently asked questions
What causes red eyes in photos?
In dim light the pupils are wide open. The camera flash, mounted close to the lens, lights up the blood-rich retina at the back of the eye and the light bounces straight back into the lens, so the pupil looks red. It is most common in small cameras and phones where the flash sits right next to the lens.
How does this red eye remover decide what to fix?
Inside the area you click or select, it measures how much stronger the red channel is than green and blue. Pixels above the sensitivity threshold that form a connected pupil-shaped blob are corrected; the red is replaced by the average of green and blue, then darkened by the Pupil darkness amount. Soft edges are blended so there is no hard outline.
Some red is still visible after fixing. What should I do?
Raise Sensitivity and click the eye again, or use a slightly larger brush. Each click is a separate step, so you can apply it twice, and Undo removes the last step if it went too far.
Will it change red lips or red clothing?
Clicks only affect the area you select, so lips and clothes stay untouched unless you click on them. Auto-fix only looks for small, round, strongly red blobs, which skips most lips and clothing, but always check the result and press Undo if needed.
Does it fix pets' green or yellow eyes?
Pets usually show a green, yellow or white eye-shine instead of red, because they have a reflective layer behind the retina. This tool targets red only, so pet eye-shine needs a paint or clone tool such as the photo editor.
Is my photo uploaded or stored?
No. The photo is processed with the Canvas API inside your browser and is never uploaded. Closing the tab discards it.
Does the download keep the full resolution?
Yes, photos up to 6000 pixels on the long side are edited and saved at their original size. Larger images are scaled down to 6000 pixels to keep the browser responsive.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.