Web Vitals Score Calculator Plug in your LCP, INP, and CLS measurements and instantly see how your page rates against Google’s Core Web Vitals thresholds. The calculator returns a Good / Needs Improvement / Poor verdict per metric, a pass/fail summary for the page, and concrete fix suggestions for anything below target — all client-side, ...
Try the Tool »Font Modular Scale Generator The Font Modular Scale Generator builds a complete typographic scale from a single base size and a chosen mathematical ratio. Each step in the scale is the previous step multiplied by the ratio, so headings, body text, and small print stay in proportion across every screen. How to Use Set the ...
Try the Tool »RC Circuit Time Constant Calculator The RC Circuit Time Constant Calculator computes τ = R × C for resistor-capacitor circuits and τ = L / R for resistor-inductor circuits, with automatic SI unit conversion. It generates a charge / discharge table at one through five time constants and tells you how long the circuit needs ...
Try the Tool »Format and Validate Prometheus PromQL Queries Instantly The PromQL Query Formatter & Validator tidies up the queries you write against Prometheus and other compatible time-series databases. Paste in a metric expression and the tool normalises spacing around binary operators, lays out aggregation, function calls and label matchers on their own lines when the query gets ...
Try the Tool »Customer Lifetime Value (CLV / LTV) Calculator Customer Lifetime Value tells you how much revenue or profit one customer is worth across the entire relationship — not just today’s order. This calculator covers both the classic e-commerce formula (Average Order Value × purchase frequency × customer lifespan) and the SaaS subscription formula (ARPU × gross ...
Try the Tool »Format R Code to the Tidyverse Style Instantly The R Code Formatter applies tidyverse and styler conventions to any R script in your browser. Paste your code and the tool fixes spacing around <- assignment arrows, comparison operators, pipe operators like %>% and |>, indents nested blocks, and flags any line that exceeds your chosen ...
Try the Tool »Calorie Burn Calculator (Exercise & MET) Find out how many calories you burn during exercise using standardized MET (Metabolic Equivalent of Task) values from the Compendium of Physical Activities. Choose from 100+ activities across cardio, sports, strength, mind-body, dance, and daily life — then enter your body weight and either how long you exercised or ...
Try the Tool »vCard Contact File Generator Build a properly formatted .vcf contact file (vCard 3.0 or 4.0) that phones, address books, and email clients accept on first import. Fill in the fields, watch the raw vCard update live, then download the file or copy the text. Everything runs in your browser — no contact data leaves the ...
Try the Tool »Solidity Code Formatter Paste your Solidity smart contract source and get back clean, style-guide-compliant code in the browser — no installs, no Hardhat config, no remote compilation. The formatter reorders function modifiers, sorts pragmas and imports, normalises NatSpec comments, and applies consistent indentation so the output is ready for review or audit hand-off. How to ...
Try the Tool »Battery Life / Runtime Calculator Estimate how long a battery will power a device from its capacity, voltage and load. The calculator handles mAh, Ah and Wh inputs, series/parallel cell arrangements, depth-of-discharge limits, system efficiency and the Peukert exponent for lead-acid chemistries. Output includes pack totals and time remaining at 100%, 80%, 50% and 20% ...
Try the Tool »cURL to Code Converter Paste a curl command and instantly get the equivalent HTTP-client code in Python, JavaScript, PHP, Go, or Ruby. The converter runs entirely in your browser, parses curl with a real shell-aware tokenizer, and maps the flags you actually use — headers, JSON and form bodies, multipart uploads, basic auth, cookies, redirects, ...
Try the Tool »Bicycle Gear Ratio & Speed Calculator See exactly how fast you will roll in every gear on your bike. Punch in your chainring and cassette teeth, pick a wheel size, and the calculator builds a colour-coded grid of speed, gear inches, development and ratio for every chainring × sprocket combination — useful when shopping for ...
Try the Tool »Braille Text Generator Convert any text into Grade 1 (uncontracted) English Braille using the official Unicode Braille block. The tool renders each character as a large 2×3 dot cell so you can see exactly which dots are raised, plus a per-character map showing the source letter alongside its Braille glyph. Useful for accessibility prototyping, classroom ...
Try the Tool »Camera Depth of Field (DoF) Calculator Plan sharp photographs with confidence. This calculator uses the exact thin-lens depth of field formulas to compute the hyperfocal distance, the near and far focus limits, and the total depth of field for any camera sensor, focal length, aperture, and subject distance. No guesswork, no approximations — just the ...
Try the Tool »SVG Noise & Texture Generator Create organic grainy noise and turbulent cloud textures directly in your browser using the SVG feTurbulence filter. Drag the sliders, tweak the seed, pick a tint color, and watch the texture update live. Export as inline SVG, a CSS background-image data URI, or a reusable SVG filter you can apply ...
Try the Tool »Text Column Aligner The Text Column Aligner pads spaces between text so a chosen delimiter — an equals sign, colon, comment marker, arrow, pipe, tab, or any custom string — lines up vertically across every row. It turns ragged key/value blocks, config snippets, and inline comments into clean visual columns without rewriting the content itself, ...
Try the Tool »Paper Size Reference & Converter Look up any standard paper size across the ISO, ANSI, and JIS systems and see its dimensions in millimeters, centimeters, inches, points, picas, and pixels at any common print or screen DPI. Switch to custom mode to enter your own width and height in mm, cm, inches, points, or pixels ...
Try the Tool »VO2 Max Estimator Calculator VO2 max is the maximum rate at which your body can take in and use oxygen during all-out exercise. It is the most widely used objective measure of aerobic (cardiorespiratory) fitness, and it scales with how hard, how long, and how often you can sustain endurance work. Reaching a true lab-grade ...
Try the Tool »Big Integer Calculator Compute exact results for math expressions that overflow ordinary calculators. The tool runs entirely on JavaScript BigInt, so factorial(1000), 25000, fibonacci(10000), and primality checks on trillion-digit candidates return every digit correctly — no scientific notation, no silent rounding. How to Use Type an integer expression, for example 2 ** 1000, factorial(100), or ...
Try the Tool »Shell Glob Pattern Tester Test glob patterns against a list of file paths and see exactly which paths match — in real time, with semantics for Bash, Zsh, .gitignore, Python fnmatch, and Go path.Match. Type a pattern like src/**/*.{js,ts}, paste paths, and watch matches highlight green and non-matches fade out as you type. How to ...
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Scoreboard is a fun way to keep track of your games, all data is stored in your browser. More features are coming soon!
Update: Our latest tool was added on Jun 26, 2026
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