Bandwidth & Download Time Calculator Calculate download time from file size and connection speed, or find the required speed to download a file within a time target. Supports all common file size units and speed presets (3G, 4G, 5G, Wi-Fi, broadband), with configurable protocol overhead percentage. How to Use Enter your file size, select your ...
Try the Tool »Vigenère Cipher Encoder & Decoder Encrypt and decrypt text using the Vigenère cipher — the classic polyalphabetic substitution cipher once called “le chiffre indéchiffrable” (the indecipherable cipher). Enter your text and a keyword to get instant results with a step-by-step visualization, interactive tabula recta, and frequency analysis. All processing happens in your browser. How to ...
Try the Tool »JSON to HTML Table Renderer Convert a JSON array of objects into a styled, interactive HTML table. Paste your JSON data and instantly see a rendered table with sortable columns, configurable styles, nested object handling, and column visibility controls. Export the result as embeddable HTML with inline CSS, CSV, or Markdown table format. How to ...
Try the Tool »Accessible Color Pair Finder Find foreground colors that meet WCAG accessibility standards for any background color. Enter a background color and the tool searches the HSL color space to generate a palette of text colors that achieve AA or AAA contrast compliance. Preview each pair with sample text, check specific color combinations, and export accessible ...
Try the Tool »SVG Sprite Sheet Generator Combine multiple SVG files into a single sprite sheet for efficient icon loading. Upload your SVGs via drag-and-drop, preview them in a grid, edit symbol IDs, and download a combined sprite file ready for production. Get usage code snippets for external, inline, and CSS background approaches. Optionally strip fills and strokes ...
Try the Tool »Video Bitrate Calculator Calculate the recommended video bitrate for any resolution, frame rate, codec, and quality level. Select from standard resolutions (480p to 8K) or enter custom dimensions, choose your codec (H.264, H.265, VP9, AV1, ProRes), set quality (streaming, high, ultra), and instantly see the recommended bitrate range. How to Use Select your target resolution ...
Try the Tool »HTTP Cookie Builder & Generator Build correct HTTP Set-Cookie headers with a visual configurator. Set name, value, domain, path, expiration, SameSite, Secure, HttpOnly, and other attributes, then get the generated Set-Cookie header, document.cookie string, and server framework code snippets. Includes a cookie parser to reverse-engineer existing Set-Cookie strings and preset configurations for common cookie types. ...
Try the Tool »Email Header Analyzer & Parser Parse and analyze raw email headers into a structured, readable format. Paste email headers to see the complete delivery path, authentication results (SPF, DKIM, DMARC), decoded MIME headers, spam analysis, and hop-by-hop timing. All processing happens in your browser — no data is sent to any server. How to Use ...
Try the Tool »Permutation & Combination Calculator Calculate permutations (nPr) and combinations (nCr) with exact results using BigInt arithmetic — no overflow even for large numbers. Enter n and r to get both values simultaneously with step-by-step formula breakdowns. Includes a Pascal’s Triangle visualizer, multiset permutation calculator, and full enumeration of all arrangements for small sets. How to ...
Try the Tool »DPI / PPI Calculator Calculate the pixel density (PPI/DPI) of any screen from its resolution and physical diagonal size. Enter width and height in pixels and the diagonal screen size in inches to instantly see pixels per inch, dot pitch, total pixel count, and a full display properties table. How to Use Enter your display’s ...
Try the Tool »Regex Flavor Converter Convert regular expressions between programming language flavors: PCRE (PHP), JavaScript, Python, Go, Java, and Ruby. Automatically converts named groups, flags, backreferences, and other syntax differences. Highlights incompatible features with clear warnings. Includes a test panel to validate your converted regex against sample strings. How to Use Enter your regex pattern, select the ...
Try the Tool »CORS Headers Builder & Validator Build correct CORS (Cross-Origin Resource Sharing) headers with a visual configurator. Set allowed origins, methods, headers, and credentials, then get the generated HTTP headers and ready-to-use code snippets for Express.js, Nginx, Apache, Django, FastAPI, Flask, and Go. Real-time validation catches common CORS misconfigurations before they reach production. How to Use ...
Try the Tool »Circle & Ellipse Calculator Calculate all properties of circles and ellipses from any known measurement. In circle mode, enter any single value — radius, diameter, circumference, or area — and get all other measurements instantly, plus sector and segment calculations for any angle. In ellipse mode, enter the semi-major and semi-minor axes to get area, ...
Try the Tool »Discount & Markup Calculator Calculate markups, margins, discounts, and pricing in one versatile tool. Five calculation modes cover every common pricing scenario: markup from cost, profit margin analysis, discount from original price, reverse discount to find the original price, and stacked discounts for multiple sequential reductions. Includes a bulk pricing table, a clear margin vs ...
Try the Tool »Running Pace Calculator Calculate running pace, speed, distance, or time from any two known values. Enter your distance and finish time to get your pace per kilometer and mile, or set a target pace to find your expected finish time. Includes race distance presets from 5K to 100K ultra, a splits table with negative split ...
Try the Tool »Body Fat Percentage Calculator Estimate your body fat percentage using two established methods: the US Navy circumference method and the BMI-based formula. Enter your measurements in metric or imperial units, select your sex, and get your estimated body fat percentage, BMI, fat mass, lean mass, and fitness category. A visual spectrum bar shows where you ...
Try the Tool »Statistics Calculator Calculate comprehensive descriptive statistics for any dataset. Paste or type a list of numbers and instantly get mean, median, mode, standard deviation, variance, quartiles, skewness, kurtosis, and more. Includes a histogram visualization, frequency distribution table, five-number summary, and the option to toggle between population and sample calculations. Export your results as CSV. How ...
Try the Tool »Compression Ratio Calculator Calculate compression ratio, space savings percentage, and size reduction from original and compressed file sizes. Enter sizes in any unit (B, KB, MB, GB, TB) and instantly see the compression ratio, bits per byte, space saved, and effective throughput metrics. How to Use Enter the original file size and its unit, then ...
Try the Tool »SSH Key Generator Generate SSH key pairs directly in your browser using the Web Crypto API. Supports Ed25519 (recommended), ECDSA P-256/P-384, and RSA 2048/4096. Your private key is generated locally and never leaves your browser. Download keys in OpenSSH format, view fingerprints, and get quick setup commands. How to Use Select your preferred algorithm (Ed25519 ...
Try the Tool »SVG Wave & Divider Generator Create beautiful SVG wave section dividers for your website. Choose from 6 wave styles — smooth sine, layered waves, sharp zigzag, rounded hills, asymmetric, and organic blob — customize amplitude, frequency, colors, and layers, then export as SVG code, CSS background, HTML snippet, or downloadable SVG file. Optional CSS animation ...
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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 May 29, 2026
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