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ChaosLens

Free browser-based tools for image processing, health calculations, keyboard and display testing, random generation, charts, unit conversion, and everyday utilities. Many tools run locally in your browser, keeping files and inputs on your device.

All Tools

69 tools available. Select one to open it here.

Arc Diagram Maker

Build an arc diagram from source, target, weight, and group data, then inspect, style, and export the result.

Centimeter, Inch, and Feet-and-Inches Converter

Convert centimeters, total inches, and feet plus inches in either direction.

GIF Frame Player

Upload a GIF to play it frame by frame, reverse the preview, inspect delays, and download the current composited frame as PNG.

Image Splitter

Split images locally by crop boxes, draggable lines, grids, or fixed pixel tiles.

Mac Keyboard Test

Test a Mac keyboard one key at a time to see which standard keyboard events the browser recognizes and find keys that are not tested or captured.

Macro Calculator

Calculate daily protein, fat, and carbohydrate targets from calories, weight, and your preferred allocation rule.

Mouse Single- and Double-Click Test

Click the test area to distinguish separate clicks, valid double-click intervals, and suspected switch bounce.

Random Number Generator

Generate random integers or decimals within a custom range, with quantity, uniqueness and sorting controls.

Carbohydrate Needs Calculator

Enter daily calories, weight, goal, training volume, and carbohydrate percentage to estimate daily carbohydrate grams, calories, and a reference range.

BMI Calculator

Calculate BMI, a healthy weight range, and adult screening categories from your height and weight.

Increase Image File Size

Increase JPG, PNG, and WebP file sizes locally without changing pixel dimensions.

Keyboard CPS Test

Choose a duration and key mode, tap quickly, and review average CPS, the one-second rolling peak, and valid key count.

List Randomizer

Paste or upload a list, clean blank and duplicate lines, then shuffle the remaining items into a new order.

Ideal Weight Calculator

Compare four classic ideal-weight formulas and the adult BMI reference range using your height and sex.

Keyboard Rollover Test

Choose a combination to press at once, then hold several keys to see which key events the browser receives at the same moment, the maximum simultaneous count, and possible missing keys.

Random Item Picker

Paste a list of items, pick one or more entries at random, and review the remaining items and draw history.

Touchscreen Test

Use Touchscreen Test in the browser for a focused display check or calculation. The page keeps the work on this device.

Body Fat Goal Calculator

Enter your current weight, body fat percentage, and daily calorie deficit to estimate your target weight, amount of fat you need to lose, and the time frame.

Coin Flip Simulator

Choose how many flips to run, simulate a fair coin, and review the running counts, observed shares, and recent rounds.

Keyboard Chatter Test

Choose a key and complete repeated press-and-release cycles to flag intervals below a threshold and review the suspected chatter rate and stability.

Black Level Test

Step through near-black patches from 1 to 32 and record the gray level that first separates from a pure-black background on your display.

Keyboard Dropout Test

Hold a target key and analyze steady-state browser auto-repeat intervals to find suspected long gaps and judge whether the sample is sufficient.

Wedding Seating Chart Maker

Add your guest list and table assignments to create a wedding seating chart, review assignments, choose a design, and print or export it as PDF.

Waist-to-Hip Ratio Calculator

Enter sex, waist circumference, and hip circumference to calculate WHR and view common WHO adult reference cutoffs and measurement guidance.

Waist-to-Height Ratio Calculator

Enter waist circumference, height, and optional age to calculate WHtR, view a continuous adult reference band, and compare waist size with half your height.

Backlight Bleed Test

Use a full-screen black display to inspect edge and corner bright spots, then record the conditions, severity, and affected regions.

Body Fat Calculator (U.S. Navy Method)

Estimate body fat percentage, fat mass, and lean mass from sex, height, weight, and body circumferences using the classic U.S. Navy method.

Keyboard Latency Test

Press a normal key repeatedly to estimate the scheduling delay from the browser event timestamp to the start of JavaScript handling, then review the median, P95, and sample distribution.

TDEE Calculator

Enter sex, age, height, weight, and activity level to estimate BMR, TDEE, and a maintenance-calorie range, with steps and training minutes to check the activity factor.

Wedding Menu Card Maker

Build a wedding menu from courses and descriptions, choose a coordinated design, optionally personalize it with guest names and meal selections, then print or export PDF.

Calorie Deficit Calculator

Enter TDEE, select fat loss, maintenance or muscle gain mode, and instantly calculate target calories, daily difference, theoretical weekly change and planning range.

Caffeine Intake Calculator

Enter drink servings, volume, and caffeine per serving to estimate daily caffeine, source shares, and an adult reference comparison.

Sugar Intake Calculator

Enter daily calories and sugar sources to calculate added sugar, free sugars, and their share of energy.

Weight loss time calculator

Enter your current weight, target weight, and weekly weight loss rate to estimate the weeks required, target date, and planning range.

Keyboard Polling Rate Test

Alternate between two ordinary keys to estimate the upper bound of the browser's non-repeat key-event frequency, then inspect P10 gaps, stability, and sample distribution. The result cannot certify hardware polling rate.

Random Letter Generator

Generate one or more random English letters while controlling case, repeats, excluded letters, and sorting.

Wedding Favor Tag Maker

Enter one or more favor-tag messages, choose copies and tag size, then generate a printable Letter sheet of wedding favor tags.

Random String Generator

Choose a length, quantity, and character set to create one or more random strings directly in your browser.

Typing Speed Test

Choose a practice passage from ChaosLens's eight default languages and measure net speed, gross speed, accuracy, uncorrected errors, corrections, and completion progress locally in your browser.

Water Intake Calculator

Estimate a daily beverage range from your weight, activity and heat or sweating, while keeping total-water AI separate.

Wedding Invitation Maker

Enter couple names, date, ceremony time, venue and RSVP details to create a printable wedding invitation.

Wedding Vendor Tip Calculator

Enter vendor costs and your chosen percent, fixed or per-person tip rules to calculate a wedding tip-envelope plan.

JavaScript Keyboard Event Tester

Focus the test area and press keys to inspect the keydown, keyup, key, code, location, repeat, modifier, composition, and timing data that this browser receives.

Random Hex Generator

Generate random hexadecimal data by exact byte count or HEX character count, with a clear view of character length, byte equivalent, and random bits.

Keyboard Repeat Rate Test

Hold a chosen key to measure the first auto-repeat delay, the steady repeat interval, and repeats per second reported by the browser, then review interval stability. The result reflects operating-system and browser events, not the keyboard's hardware polling rate.

Keyboard Layout Detector

Sample the browser's code-to-key mapping, compare five candidate character layouts, and review the leading layout, conflicts, and confidence. Operating-system settings are not read.

Color Banding Test

Compare controlled gradients, quantization, and dithering to record visible bands, level jumps, or grain on a display.

Hotkey and Combination Tester

Choose a shortcut combination and press it in the capture area to see whether this browser receives every target key, left/right modifier, and extra key.

Keyboard Layout Analyzer

Enter Latin text or recorded key sequences to compare QWERTY, Dvorak, and Colemak by key frequency, finger load, and adjacent-key patterns.

Monitor Color Accuracy Test

Use reference patches for a visual cast check, or enter measured Lab data to calculate CIEDE2000 ΔE00.

Key Hold Duration Test

Hold a chosen key and release it repeatedly to measure the duration of each browser keyboard event.

Dead Pixel Test

Clean the screen, switch through six full-screen solid colors, and mark the locations of fixed bright, dark, or stuck-color pixels.

Grayscale Test

Display discrete grayscale, near-black, and near-white levels to record which adjacent steps remain distinguishable, along with neutral color cast and regional unevenness.

Remove Prefixes from Words

Remove a chosen prefix from detected words while leaving other text and separators in place.

Monitor Color Test

Show controlled colors and gradients full-screen to check dead pixels, tint, uniformity, and visible rendering issues.

Monitor Color Calibration Guide

Follow a practical five-step monitor setup for brightness, contrast, gamma, white point, RGB balance, and a final visual check.

Monitor Color Gamut Test

Compare browser-reported sRGB, Display-P3, and Rec.2020 support with color patches, gradients, and a readiness checklist.

Monitor Contrast Test

Use black, white, window, and checker patterns to inspect shadow detail, highlight clipping, and perceived contrast.

Red Screen

Use Red Screen in the browser for a focused display check or calculation. The page keeps the work on this device.

Green Screen Test

Open a pure green fullscreen to inspect the green channel, pixel anomalies, and large-area uniformity, with optional framing guides.

Blue Screen

Show a standard pure-blue background in one click, enter full screen, and optionally leave automatically after a timer.

Gray Screen Test

Show calibrated gray levels in fullscreen to observe panel uniformity, tint, and near-black behavior.

Orange Screen

Use Orange Screen in the browser for a focused display check or calculation. The page keeps the work on this device.

4:4:4 Chroma Subsampling Test

Render colored text and one-pixel patterns to visually check whether a display path preserves chroma detail.

LCD Pixel Inversion Test

Show high-frequency alternating pixel patterns and record visible flicker, scan lines, or pixel-walk effects on an LCD.

Display Test Card Generator

Choose a resolution and test layers to create PNG or SVG cards for TVs, monitors, and projectors.

Square GIF Maker

Upload a GIF, choose the effect or layout you want, and create a new animation locally in your browser with Square GIF Maker.

Single-Frame GIF Generator

Set the options for Single-Frame GIF Generator and generate the animation locally in your browser; no source file is required.

1×1 Pixel GIF Generator

Set the options for 1×1 Pixel GIF Generator and generate the animation locally in your browser; no source file is required.