Textile & Yarn Converter Cross-reference knitting needle sizes, crochet hook sizes, and yarn weight categories across US, UK/Canada, metric, and Japanese standards in one place. Useful when a pattern from one country lists a needle or yarn name that does not match what is printed on your local supplies. How to Use Pick a category ...
Try the Tool »Network Speed Unit Converter Instantly convert between every common network and data transfer rate unit – bps, Kbps, Mbps, Gbps, Tbps, B/s, KB/s, MB/s, GB/s, TB/s, plus the binary IEC units like KiB/s and MiB/s. Type a value into any field and every other field updates live, so you never have to guess whether a ...
Try the Tool »ICS Calendar Event Generator Build a standards-compliant .ics calendar file in seconds, then download it or copy the raw iCalendar text. Fill in the event details, choose a timezone and an optional repeat rule, add a reminder, and you get a clean RFC 5545 file that imports cleanly into Apple Calendar, Google Calendar, Outlook, Fastmail, ...
Try the Tool »Stack Trace Formatter & Parser Paste a raw stack trace from JavaScript, Python, Java, Ruby, Go, .NET, or PHP and instantly get a colour-coded, frame-by-frame breakdown. The tool auto-detects the language, separates your code from framework noise, and produces a clean Markdown block that you can drop straight into a bug report or pull request. ...
Try the Tool »Macronutrient Calculator Turn a daily calorie goal into precise gram targets for protein, carbohydrates, and fat — split exactly the way you eat. Pick a preset diet (balanced, high protein, keto, endurance, zone) or drag the sliders to a custom split, then choose how many meals you eat per day. The calculator instantly returns grams ...
Try the Tool »Calculate the total floor area, the exact number of tiles, and the boxes to buy for any rectangular or L-shape room - with grout gap, wastage allowance, and metric / imperial units.
Try the Tool »Mock HTTP Response Builder Construct a structurally correct HTTP response message in seconds. Pick a status code, choose a body type, add headers, and the tool emits a ready-to-paste response string with the status line, headers, and body separated by CRLF — perfect for test fixtures, integration mocks, API documentation, and replaying responses against clients. ...
Try the Tool »QR Code Reader / Decoder Decode any QR code image directly in your browser. Drop a screenshot, photo, or saved image into the uploader and the tool returns the embedded text, URL, Wi-Fi credentials, contact card, or other payload — instantly and without sending the image anywhere. How to Use Click the upload area and ...
Try the Tool »Molar Mass Calculator Type a chemical formula and get the exact molar mass in g/mol, a per-element breakdown, and the mass percentage of each element. Atomic weights use IUPAC 2021 standard values so results are reliable for laboratory and coursework use. Parentheses, polyatomic groups, and hydrate notation (CuSO4·5H2O) are fully supported. How to Use Enter ...
Try the Tool »Docker Compose YAML Formatter Paste a docker-compose.yml and instantly get a clean, consistently formatted file with services, networks, and volumes ordered the way Docker Compose conventions expect. The formatter validates the file against the modern Compose Spec, flags deprecated keys like the old top-level version field or legacy links, and warns about unknown service options ...
Try the Tool »Barcode Check Digit Validator Validate the check digit of any retail or shipping barcode in one paste. The validator auto-detects the format from the digit count, recomputes the expected check digit using the right algorithm — GS1 modulo-10 for EAN/UPC/GTIN, modulo-11 for ISBN-10 — and shows a position-by-position breakdown so you can see exactly where ...
Try the Tool »MIME Type Interactive Lookup Look up the correct MIME type for any file extension — or find the file extensions associated with a MIME type. Built on the IANA media type registry, this interactive lookup gives you instant, accurate results with category labels and one-click copying so you can drop the right Content-Type into your ...
Try the Tool »Country Info Lookup Look up authoritative metadata for every country in the ISO 3166-1 standard — names, codes, dialing prefixes, currencies, capitals, and TLDs — in one place. The tool ships with a bundled dataset of 249 countries and dependent territories, so every search is instant, accurate, and works fully offline in your browser. Unlike ...
Try the Tool »Time Zone Meeting Planner Find the best meeting window across multiple time zones at a glance. Add up to eight cities or IANA zones, pick a meeting date, and a color-coded 24-hour grid shows business hours, marginal slots, and night hours for every participant. Click any cell to lock in a moment and copy a ...
Try the Tool »Luminance & Illuminance Unit Converter Convert between every common photometric unit on one screen, with illuminance and luminance kept clearly apart so you never accidentally swap lux for nits. Type a value in any field and the rest of its group updates instantly. Why Two Groups Instead of One Illuminance (lux, foot-candle, phot, millilux, nox) ...
Try the Tool »Convert Force Units Instantly Engineers, physics students, and machinists work with force in a baffling mix of units: newtons in SI papers, pound-force in US torque specs, kilogram-force in old European drawings, and dynes in CGS textbooks. The Force Unit Converter handles them all in one screen — change any value and every other unit ...
Try the Tool »Water & Liquid Tank Volume Calculator Calculate the total and partial-fill volume of any storage tank from a few simple dimensions. Pick the tank shape, type the dimensions in your preferred unit, and instantly read the capacity in liters, US and UK gallons, cubic meters, cubic feet, and US fluid ounces. The calculator also estimates ...
Try the Tool »Survey Sample Size Calculator Figure out how many people you need to survey to get reliable results. The Survey Sample Size Calculator turns Cochran’s formula into a one-click answer, supports finite populations with the appropriate correction, and shows a sensitivity table so you can see exactly how the requirement shifts as your margin of error ...
Try the Tool »A/B Test Statistical Significance Calculator Drop in the visitors and conversions for your Control (A) and Variant (B) and instantly see whether the difference between them is real or just noise. The calculator runs a two-proportion z-test, computes the p-value, the absolute and relative lift, and the confidence interval for the difference, then turns the ...
Try the Tool »Container Garden Planner & Spacing Calculator Plug in your pot size and the plant you want to grow, and instantly see how many will fit, how much potting mix to buy, whether the container is deep enough, and which neighbours will help (or hurt) your harvest. Built for balcony gardeners, apartment growers and tabletop herb ...
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Update: Our latest tool was added on Jun 3, 2026
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