Page Speed Simulator - Online Estimate Load Metrics
Enter a URL and get a rough client-side performance simulation: request count, DOM size, and potential speed tips. No real Lighthouse.
UD5 Toolkit
Estimate how long it takes to read any text. Paste your content, adjust your reading speed, and get an instant time estimate.
Enter a URL and get a rough client-side performance simulation: request count, DOM size, and potential speed tips. No real Lighthouse.
Quickly estimate your internet connection speed by downloading a small test file. See class and recommendations.
Calculate swim pace per 100m or 100yd based on total time and distance. Predict race times. For pool and open water swimmers.
Measure your internet connection speed by downloading and uploading a small test file. Works from your browser.
Enter hole saw diameter and material to find the recommended RPM and feed pressure. Prevent burning and kickback.
Compute multiple readability scores (Flesch Reading Ease, Grade Level, ARI, SMOG). Paste any English text and see which grade level it's suitable for. Local.
Estimate hiking time using Naismith's rule (distance + elevation gain). Adjust for terrain and fitness. Plan your outdoor adventure.
Morse characters flash on screen; you must tap them correctly on a single button. Points for accuracy and speed. Learn Morse in a fun way.
Compute the selling price from cost and desired markup percentage, or find the markup from cost and price.
Tap any key multiple times. Shows average BPM, standard deviation, and a visual metronome beat. More accurate than simple tap.
Compare text‑rendering: auto, optimizeSpeed, optimizeLegibility, geometricPrecision. See kerning and ligature changes live.
Enter your current savings, monthly contribution, and target amount. Calculate time needed and suggestions. Private.
Based on desired annual income and billable days, calculate your minimum day rate. Don't undercharge.
Shows a counter of how many seconds you have been idle. Tracks mouse and keyboard activity without recording.
A beautiful full‑screen binary clock showing hours, minutes, seconds in glowing bits. Dark mode perfect for desks.
Analyze letter/symbol frequency with an interactive bar chart and heatmap. Useful for breaking simple ciphers, linguistics, and SEO keyword analysis. Local processing.
See how many years it takes to double your money at a given interest rate using the Rule of 72. Quick financial math.
Paste text with mixed Arabic/Hebrew and English. See the Unicode bidi class of each character and ordering. i18n debugger.
Enter vehicle price, down payment, rate, term to compute monthly payment and total interest paid.
Random letters appear; you must type the correct code word quickly. Beat your high score. Learn the NATO alphabet.
Enter distance and time to get your 500m split. Also predicts how a change in stroke rate affects power output.
Convert fuel economy units between miles per gallon (US/UK), liters per 100 km, and kilometers per liter. Useful for international car comparisons.
Enter daily steps and weight to see approximate calories burned. No tracking, just convert.
Set a target weight and see estimated daily calorie deficit needed. Computes safe timeline based on 500-1000 kcal deficit. Includes BMR & TDEE estimation. Fully local.
Paste text to accurately count sentences, average sentence length, and longest sentence. For editors and writers.
Calculate your ideal hourly rate based on target annual income, expenses, holidays, and non-billable time. Compare with project-based pricing. Local only.
Calculate the break‑even point in units and dollars. Input fixed costs, variable cost per unit, and price.
Enter a reference port's high tide and see estimated tides for the next 3 days using rule of twelfths. Educational.
Determine how many calories your cat should eat based on ideal weight, activity, and body condition.
Calculate the new average cost of a stock after buying more shares at a different price. Invest smarter. All local.