IshiharaTest.com is a free, no-sign-up online Ishihara color blindness screening test. Based on the classic Ishihara plate method, it gives a fast, private indication of whether you may have a red-green color vision deficiency, along with a difficulty breakdown and a downloadable PDF report.

It runs on any device and is available in 13 languages, which makes it one of the most accessible color-vision tools for international audiences. There is no account, no payment, and no email gate.

Beyond the test itself, the site includes a plain-language guide to color vision deficiency: how the eye's L, M and S cones work, the differences between protanopia, deuteranopia and tritanopia (and their milder anomalous forms), causes and inheritance, and how the condition is detected. The content is written to be genuinely useful to patients, parents, teachers, designers and HR teams.

Importantly, the test is presented transparently as a screening tool. It indicates a possible deficiency but is not a medical diagnosis, and users are always directed to a qualified optometrist or ophthalmologist for confirmation.

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Cachely is the managed self-hosted remote cache for Nx and Turborepo - the cache backend you'd otherwise build and run yourself, hosted for you on Cloudflare's edge (R2). It's a drop-in replacement for a DIY @nx/s3-cache / S3 bucket setup: point your build tool at Cachely with a token and two environment variables, and share build cache across CI and every developer's laptop.

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