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 »Wavelength & Frequency Calculator Convert between wavelength (λ) and frequency (f) for any electromagnetic wave — radio, microwave, infrared, visible light, ultraviolet, X-ray, or gamma. Enter either value, choose a unit, and instantly see the corresponding frequency or wavelength, the photon energy in eV and joules, and the position of your value on a log-scaled ...
Try the Tool »Quadratic Formula Solver Enter the coefficients a, b, and c of any quadratic equation in the form ax² + bx + c = 0 and instantly get the discriminant, the two roots (real or complex), the vertex, the axis of symmetry, the vertex form, a step-by-step derivation, and a visual sketch of the parabola. Everything ...
Try the Tool »Open Graph Social Card Image Generator Design pixel-perfect social share images for Open Graph, Twitter Cards, LinkedIn, and Facebook directly in your browser. Type your title, description, and site name, pick a layout and theme, then download a PNG, JPG, or WebP at the exact dimensions each platform expects — no design tool or upload ...
Try the Tool »Gradient Text CSS Generator Design eye-catching text effects with multi-color gradients and copy production-ready CSS in a single click. Pick your colors, choose linear or radial, watch the live preview update, then drop the snippet into your stylesheet. How to Use Type the sample text you want to preview. Set the font size and weight ...
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 »CSS Neumorphism Generator Build soft, extruded “neumorphic” UI elements without hand-tuning two opposing box-shadows. Pick a base color, choose a shape (flat, concave, convex, or pressed), drag the sliders for distance, intensity, blur, and light angle, then copy the generated CSS straight into your project. How to Use Pick a background color. The same color ...
Try the Tool »ECDSA / Ed25519 Key Generator Generate cryptographically secure elliptic-curve key pairs in your browser using the Web Crypto API. Pick Ed25519, ECDSA P-256, or ECDSA P-384, and export in PEM (PKCS8/SPKI), JWK, or raw hex format. Useful for JWT signing (ES256, EdDSA), Signal-style protocols, libsodium interop, and any general-purpose elliptic-curve cryptography that is not OpenSSH-flavored. ...
Try the Tool »PKCE Code Verifier & Challenge Generator Generate RFC 7636-compliant PKCE values right in your browser. Pick a verifier length (43–128 characters), and the tool produces a cryptographically random code_verifier together with the matching SHA-256 code_challenge in base64url form, ready to drop into any OAuth 2.0 or OAuth 2.1 authorization request. Useful for SPAs, mobile apps, ...
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 ...
Try the Tool »Recipe Scale Calculator Halve a cookie recipe for a smaller batch, double a soup to feed a crowd, or convert a 4-portion family dinner into a 12-person dinner party. The Recipe Scale Calculator takes any ingredient list, multiplies every quantity by your serving ratio, and prints a clean, copy-ready scaled recipe — with smart fractions ...
Try the Tool »SAML Response Decoder Paste a base64-encoded SAML response or assertion and instantly see the decoded XML alongside a summary of the most important fields. Handles URL-encoded payloads and DEFLATE-compressed strings used by SAML’s HTTP-Redirect binding, all in your browser — nothing is uploaded. How to Use Capture the SAML response from your IdP — usually ...
Try the Tool »XML to CSV Converter Paste any XML document and convert its repeating records into a flat CSV file. The tool auto-detects the row element and the columns from element tags and attributes, previews the first 10 rows, and lets you download the full CSV — useful for migrating data out of legacy systems, exports, or ...
Try the Tool »Cocktail Measurement Converter Convert between bar and kitchen volume units in real time. Type a value into any field and every other field updates instantly — milliliters, centiliters, liters, fluid ounces, teaspoons, tablespoons, cups, pints, plus cocktail-specific pours like barspoon, dash, splash, pony, jigger, shot, and double. Designed for bartenders, home mixologists, and anyone who ...
Try the Tool »Break-Even Point Calculator Find out exactly how many units you need to sell before a product or service stops losing money. Enter fixed costs, variable cost per unit, and sale price per unit, and the calculator returns break-even units, break-even revenue, contribution margin, and a profit/loss table at volumes ranging from zero to twice the ...
Try the Tool »Code Screenshot Generator Turn any snippet of code into a beautiful, shareable PNG image. Pick a syntax theme, choose a gradient background, add macOS or Windows window chrome, and download a polished screenshot ready for Twitter, LinkedIn, blog posts, slide decks, or documentation. Everything runs locally in your browser, so your code never leaves your ...
Try the Tool »Character Frequency Analyzer Paste any text and instantly see how often every character appears. The Character Frequency Analyzer counts every letter, digit, or symbol, ranks them, shows percentages, and renders a visual bar chart so you can spot patterns at a glance. It is a go-to companion for cryptanalysis, linguistics homework, password audits, content audits, ...
Try the Tool »LaTeX Equation Renderer Type or paste any LaTeX math expression and instantly see it rendered as a clean, publication-quality equation in your browser. Whether you are writing a research paper, building course material, or sharing math on social media, the LaTeX Equation Renderer turns dense source markup into a beautifully typeset formula you can copy ...
Try the Tool »Pet Age Calculator (Dog & Cat) Convert your dog or cat’s age into human-equivalent years using research-backed formulas. Dogs use the 2019 epigenetic-clock formula (16 × ln(age) + 31) — not the outdated × 7 myth — adjusted for breed size. Cats use the standard 15-9-4 rule from veterinary literature. The result card tells you ...
Try the Tool »Mermaid Diagram Renderer Paste mermaid.js syntax and instantly see a live, interactive diagram you can copy or download. Supports flowcharts, sequence diagrams, Gantt charts, pie charts, class diagrams, and more — all rendered client-side in your browser, with no servers, accounts, or installs required. Mermaid is great for “diagrams as code”: your diagram lives next ...
Try the Tool »Add IO tools to your favorite browser for instant access and faster searching
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 12, 2026
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