This category groups 5 tools around a shared workflow so users can compare related tools, navigate laterally, and find the right next step faster.
Rather than treating each utility as a one-off page, this hub gives broader context through tools like Visual Acuity Test, Eye Chart Simulator (Snellen), and Color Blindness Test and keeps internal linking stronger across the site. Looking for something adjacent? Jump back to all categories or explore popular tools like JSON Formatter, QR Code Generator and BMI Calculator.
Category hubs should explain the shape of the workflow, not just repeat tool titles. This section adds practical context for users and improves the page beyond a thin index.
Estimate a rough Snellen-style visual acuity result such as 20/20 or 20/40 from the smallest line you can read. Get decimal acuity, logMAR context, screening guidance, and practical next steps for a home-style vision check.
Display a responsive Snellen-style eye chart on screen with full-chart and single-line modes, scaling controls, mirrored view, contrast options, and distance presets for rough home-style vision screening practice.
Take a quick Ishihara-style color blindness test on screen using hidden-number dot plates. Get a rough color vision screening summary, answer pattern signals, and practical next steps for follow-up.
Use a clock-dial style astigmatism test to check whether some line orientations look darker, sharper, or blurrier than others. Get a rough screening summary and practical follow-up guidance for home eye checks.
Check how small a line of text you can read comfortably at a near reading distance. Get a rough reading-card style near vision summary and practical next-step guidance for home screening.
Format, validate, minify, or sort JSON data with configurable indentation. Instantly check for syntax errors, view node count and nesting depth — free, no sign-up required.
Generate QR codes for URLs, text, Wi-Fi credentials, vCards, and more. Customise foreground and background colour, error correction level, margin, and download as SVG or PNG — free and instant.
Calculate your Body Mass Index, healthy weight range and ideal weight using metric or imperial units.
Estimate daily calorie needs based on age, gender, height, weight and activity level using Mifflin-St Jeor, Harris-Benedict or Katch-McArdle formulas.