Ruby Code Formatter Paste your Ruby code and instantly reformat it to follow standard Ruby style: 2-space indentation, consistent operator spacing, trimmed trailing whitespace, and tidy block structure. The formatter runs entirely in your browser, so your code never leaves your machine. How to Use Paste your Ruby source into the input area, or click ...
Try the Tool »Email Deliverability Checker Audit a domain’s email authentication setup in seconds. Enter any domain and the tool runs live DNS lookups against Cloudflare’s resolver to inspect SPF, DMARC, MX, and BIMI records, then surfaces real configuration problems with a clear pass/fail verdict and an overall deliverability score. How to Use Type the domain you want ...
Try the Tool »Kotlin Code Formatter Paste any Kotlin source and get a clean, ktlint-style reformat in your browser. The formatter normalizes indentation, fixes operator spacing, sorts imports, and adds trailing commas in multi-line lists, all without sending code to a server. How to Use Paste your Kotlin code into the input box, or click Try an example ...
Try the Tool »Image Print Size Calculator Convert pixel dimensions to physical print size, or work backwards to find the pixel resolution you need for a target print. The calculator pairs the math with a quality-rating table so you can see at a glance whether your image is sharp enough for a 4×6 photo, an A4 print, or ...
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 »LED Resistor Value Calculator Pick the right current-limiting resistor for any LED circuit. Enter your supply voltage, the LED’s forward voltage and forward current, and this calculator returns the exact resistance, the nearest E12 and E24 standard values, the power dissipation, the recommended wattage rating, and a 4-band color-code drawing of the resistor you need ...
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 »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 »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 Jun 26, 2026
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