Screening
Find out what you see.Pseudoisochromatic screening
A number is hiding in each circle. Type what you see, or say you don't see one. That's a real answer and it counts.Each plate contains a figure rendered in hues separated along a specific confusion axis. Report the digits you perceive, or indicate that no figure is legible.
Why this isn't a diagnosisMethodological limitations
This isn't a diagnosis and it can't be. Your screen isn't color-calibrated, mine isn't either, and the brightness slider alone can change your answers. What this is good for is working out which conversation to have next.This screening runs on uncalibrated consumer displays with unknown gamma, white point, and ambient conditions, none of which are controlled. It is not equivalent to a clinical Ishihara examination and cannot be used diagnostically. Treat the result as an indication, not a finding.
These plates are generated from scratch rather than scanned from a book, so they look a little different to the ones you may have seen at the optician. They work the same way.Plates are procedurally generated pseudoisochromatic figures. Dot colors are sampled either side of the relevant confusion line rather than reproduced from the Ishihara series.
Your result
You read all of them.No deficiency indicated
As far as this test can tell, you see color the way most people do. Which means the rest of this site is for understanding somebody else, so go turn the filters on and see what they've been trying to describe to you.Responses are consistent with normal trichromatic vision across the plates presented. The simulator below applies the same transforms to arbitrary images, which is the more useful function of this tool for an unaffected observer.
Show me what that looks likeOpen the simulator with this filter applied
Your result
You're red-green colorblind, the common kind.Consistent with deuteranomaly
Your green sensitivity has drifted toward red, so the two crowd each other. Traffic light greens look white-ish. Olive and brown are the same paint. Someone will hand you a pink highlighter and call it red and you will have no way to argue. You're in the largest group there is: about one in twelve men.Deuteranomaly: the M-cone peak sensitivity is shifted toward longer wavelengths, reducing the separation between M and L cone responses. Red-green discrimination is compressed while overall color perception is preserved. Prevalence is approximately 5% of males, making it the most common form of color vision deficiency.
A light touchMild anomalous trichromacy
A real gapModerate anomalous trichromacy
A wide gapStrong anomalous trichromacy
About as far as this goesAt or near dichromacy
This sits toward the mild end. The plates that only trip up a serious shift still read fine for you, it's mainly the closest calls that blur. Day to day, that's things like an unlabeled traffic light in bad light, or a stain versus a shadow, more than the obvious stuff.You read the plates calibrated to fail only near full dichromacy and missed the ones calibrated to fail at the first sign of any anomaly, consistent with a mild deuteranomaly or protanomaly rather than a severe one.
This is a genuine, everyday gap, not just the edge cases. Ripe versus unripe, a lot of clothing colour-matching, some produce and some graphs, these are where it shows up regularly, not just under bad lighting.You missed plates across a meaningful middle stretch of the calibrated severity range, consistent with a moderate shift in cone sensitivity rather than a marginal or a severe one.
Most of the red-green range is genuinely hard for you. Only the widest, most obvious colour differences reliably land, the kind of gap a colleague or partner should just know about rather than assume.Only the plate grade calibrated to fail solely near full dichromacy still read correctly, indicating a substantial anomalous trichromacy well past the moderate range.
Even the plates built to be readable by almost anyone with this kind of colorblindness didn't land. This is close to the strongest signal this kind of test can show on a home screen.You missed the plate grade calibrated to hold up until severity approaches full dichromacy, the strongest signal this screening architecture can register.
I'm reporting a range, not a percentage, because the plates only tell me which ones you could still read, not a precise measurement, and a screen that isn't colour-calibrated can't give you one anyway.Severity is inferred from which calibrated plate grades were read correctly, not measured directly, so this reports a band rather than a spuriously precise percentage.
One caveat: this test is sure about the red-green part and not sure which half of it. There are two, and the one above is the common one, so it is the better bet. A real optometrist can settle it in about a minute.The deficiency axis is indicated but the diagnostic plates did not separate protan from deutan at this severity. Deuteranomaly is reported on prevalence grounds (roughly 5% of males versus 1%). Anomaloscopy resolves the distinction definitively.
Your result
You're red-green colorblind, on the red side.Consistent with protanomaly
Same family as the common kind, different half. Reds go dark on you. A red car in shade can read almost black, and red text on a dark background can vanish entirely. Red and green still run together, but it's the dimness of red that tends to give this one away.Protanomaly: reduced L-cone sensitivity, shifting peak response toward shorter wavelengths. In addition to compressed red-green discrimination, long-wavelength stimuli appear substantially darker than to a typical observer, a luminance effect absent in deuteranomaly. Prevalence is approximately 1% of males.
A light touchMild anomalous trichromacy
A real gapModerate anomalous trichromacy
A wide gapStrong anomalous trichromacy
About as far as this goesAt or near dichromacy
This sits toward the mild end. The plates that only trip up a serious shift still read fine for you, it's mainly the closest calls that blur. Day to day, that's things like an unlabeled traffic light in bad light, or a stain versus a shadow, more than the obvious stuff.You read the plates calibrated to fail only near full dichromacy and missed the ones calibrated to fail at the first sign of any anomaly, consistent with a mild deuteranomaly or protanomaly rather than a severe one.
This is a genuine, everyday gap, not just the edge cases. Ripe versus unripe, a lot of clothing colour-matching, some produce and some graphs, these are where it shows up regularly, not just under bad lighting.You missed plates across a meaningful middle stretch of the calibrated severity range, consistent with a moderate shift in cone sensitivity rather than a marginal or a severe one.
Most of the red-green range is genuinely hard for you. Only the widest, most obvious colour differences reliably land, the kind of gap a colleague or partner should just know about rather than assume.Only the plate grade calibrated to fail solely near full dichromacy still read correctly, indicating a substantial anomalous trichromacy well past the moderate range.
Even the plates built to be readable by almost anyone with this kind of colorblindness didn't land. This is close to the strongest signal this kind of test can show on a home screen.You missed the plate grade calibrated to hold up until severity approaches full dichromacy, the strongest signal this screening architecture can register.
I'm reporting a range, not a percentage, because the plates only tell me which ones you could still read, not a precise measurement, and a screen that isn't colour-calibrated can't give you one anyway.Severity is inferred from which calibrated plate grades were read correctly, not measured directly, so this reports a band rather than a spuriously precise percentage.
One caveat: this test is sure about the red-green part and not sure which half of it. There are two, and the one above is the common one, so it is the better bet. A real optometrist can settle it in about a minute.The deficiency axis is indicated but the diagnostic plates did not separate protan from deutan at this severity. Deuteranomaly is reported on prevalence grounds (roughly 5% of males versus 1%). Anomaloscopy resolves the distinction definitively.
Your result
You're on the blue-yellow side, which is rare.Consistent with tritanomaly
This one's unusual, and unlike the red-green kinds it turns up about equally in everyone. Blue and green blur together, and yellow can wash out toward pink or grey. Worth mentioning to an actual optometrist, because tritan results sometimes point at something acquired rather than something you were born with.Tritanomaly: reduced S-cone sensitivity, compressing blue-yellow discrimination. Unlike the protan and deutan forms it is not X-linked and occurs at similar rates across sexes. Acquired tritan defects can accompany retinal or optic nerve pathology, so a genuine tritan result warrants clinical follow-up rather than reassurance.
A light touchMild anomalous trichromacy
A real gapModerate anomalous trichromacy
A wide gapStrong anomalous trichromacy
About as far as this goesAt or near dichromacy
This sits toward the mild end. The plates that only trip up a serious shift still read fine for you, it's mainly the closest calls that blur. Day to day, that's things like an unlabeled traffic light in bad light, or a stain versus a shadow, more than the obvious stuff.You read the plates calibrated to fail only near full dichromacy and missed the ones calibrated to fail at the first sign of any anomaly, consistent with a mild deuteranomaly or protanomaly rather than a severe one.
This is a genuine, everyday gap, not just the edge cases. Ripe versus unripe, a lot of clothing colour-matching, some produce and some graphs, these are where it shows up regularly, not just under bad lighting.You missed plates across a meaningful middle stretch of the calibrated severity range, consistent with a moderate shift in cone sensitivity rather than a marginal or a severe one.
Most of the red-green range is genuinely hard for you. Only the widest, most obvious colour differences reliably land, the kind of gap a colleague or partner should just know about rather than assume.Only the plate grade calibrated to fail solely near full dichromacy still read correctly, indicating a substantial anomalous trichromacy well past the moderate range.
Even the plates built to be readable by almost anyone with this kind of colorblindness didn't land. This is close to the strongest signal this kind of test can show on a home screen.You missed the plate grade calibrated to hold up until severity approaches full dichromacy, the strongest signal this screening architecture can register.
I'm reporting a range, not a percentage, because the plates only tell me which ones you could still read, not a precise measurement, and a screen that isn't colour-calibrated can't give you one anyway.Severity is inferred from which calibrated plate grades were read correctly, not measured directly, so this reports a band rather than a spuriously precise percentage.
One caveat: this test is sure about the red-green part and not sure which half of it. There are two, and the one above is the common one, so it is the better bet. A real optometrist can settle it in about a minute.The deficiency axis is indicated but the diagnostic plates did not separate protan from deutan at this severity. Deuteranomaly is reported on prevalence grounds (roughly 5% of males versus 1%). Anomaloscopy resolves the distinction definitively.
Your result
That didn't tell us much.Inconclusive
Your answers didn't land in any clear pattern. That happens. A dim screen, a phone at an angle, or just a plate that was ambiguous for you. Try again somewhere brighter, or skip ahead and explore the simulator directly.Responses did not cluster along a single confusion axis. Common causes include display brightness, off-axis viewing, and ambient light. Re-testing under better conditions or proceeding directly to the simulator are both reasonable next steps.
Show me what that looks likeOpen the simulator with this filter applied
Your result
Let's blame the screen first.Viewing conditions outside usable range
One of these circles has a number in it that everybody can read: colorblind, not colorblind, all of us. You didn't get that one, which almost always means the screen rather than your eyes. Turn the brightness up, come off night mode or any blue-light filter, and look at it straight on rather than at an angle. If you try again in better light and still can't find that first number, that is worth mentioning to an optometrist.The control plate separates on luminance rather than hue and is legible under normal trichromacy and under every deficiency simulated here. A miss indicates display or ambient conditions outside the usable range: reduced backlight, an active color-temperature filter, or off-axis viewing on a low-quality panel. Re-run under corrected conditions. A repeated miss under adequate conditions warrants clinical assessment rather than further screening here.
Show me what that looks likeOpen the simulator with this filter applied
What they'll seeRecipient view
This is the page your link opens, exactly as they get it.Live render of the destination page for the generated URL.