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Desarrollador (15)
Codificador y decodificador Base64 online gratis
Codifica texto a Base64 o decodifica Base64 a texto. Variante URL-safe soportada. Todo en tu navegador — sin subida, sin seguimiento.
Conversor de Markdown a HTML online gratis — CommonMark + GFM
Convierte Markdown a HTML con vista previa en vivo. Soporta CommonMark y GitHub Flavored Markdown (tablas, bloques de código, tachado). Copiar o descargar. 100% en el navegador.
Formateador, validador y minificador JSON en línea gratis
Formatea, valida, embellece y minifica JSON en tu navegador. Rápido, gratis, sin subida, sin seguimiento. Indentación, ordenación de claves y copia al portapapeles.
Free online CSS minifier — strip comments, whitespace, redundancies
Minify CSS in your browser. Removes comments, whitespace, last semicolons; collapses 0px to 0; shortens hex colours. Live byte-saving stats. No upload.
Free online CSV ↔ JSON converter — paste, parse, copy
Convert CSV to JSON or JSON to CSV in your browser. Custom delimiter, header row toggle, RFC 4180 quoting. Runs entirely in your browser.
Free online HTML minifier — strip comments, collapse whitespace
Minify HTML in your browser. Strip comments, collapse whitespace between tags, remove default attributes. Preserves <pre>, <script>, <style>. No upload.
Free online JS minifier — strip comments and whitespace
Minify JavaScript in your browser. Removes // and /* */ comments, collapses whitespace, preserves strings and regex literals. Live byte-saving stats. No upload.
Free online JWT decoder — inspect header, payload and claims
Decode JSON Web Tokens in your browser. See the header, payload and signature, with claim-by-claim breakdown and live expiry check. No upload, no tracking.
Free online text diff checker — compare two texts side by side
Compare two pieces of text and see exactly which lines were added, removed or kept. Ignore whitespace or case. Runs entirely in your browser, no upload.
Free online Unix timestamp converter — epoch, ISO 8601, timezones
Convert Unix timestamps to ISO 8601 and human-readable dates across any IANA timezone, instantly. Live current time, copy in one click. Runs in your browser.
Free online XML formatter and validator — pretty-print or minify
Format, validate and minify XML documents in your browser. Pretty-print with chosen indent, native parser validation, declaration preserved. No upload.
Free online YAML ↔ JSON converter — paste, convert, copy
Convert YAML to JSON or JSON to YAML in your browser. Live preview, indent options, validation. Useful for Kubernetes, GitHub Actions, Docker Compose configs.
Generador de hash online gratis — SHA-1, SHA-256, SHA-384, SHA-512
Calcula hashes SHA-1, SHA-256, SHA-384 y SHA-512 de cualquier texto al instante. Impulsado por la API Web Crypto nativa del navegador. Sin subida, sin seguimiento.
Generador de UUID online gratis — v4, v7 y nil
Genera UUIDs v4 criptográficamente aleatorios, UUIDs v7 ordenables por tiempo o el UUID nil al instante en tu navegador. Generación en bulk hasta 100 IDs de una vez. Sin subida, sin seguimiento.
Probador de regex online gratuito — playground de regex JavaScript
Prueba expresiones regulares JavaScript en tu navegador. Coincidencias en vivo, grupos de captura, vista previa de reemplazo y biblioteca de patrones comunes. Sin subida, sin seguimiento.
Web y SEO (6)
Codificador y decodificador de URL online gratis
Codifica texto en formato porcentaje para inclusión segura en URL, o decodifica cadenas porcentaje. Modo Componente o URL completa. 100% en el navegador.
Free online HTML entity encoder and decoder
Encode special characters as HTML entities or decode them back to plain text. Minimal, named or full numeric encoding. Runs entirely in your browser.
Free online HTML meta tag generator — SEO, Open Graph, Twitter Card
Generate SEO meta tags, Open Graph tags, Twitter Card tags and canonical link from a single form. Copy ready-to-paste HTML for your <head>. Runs in your browser.
Free online robots.txt generator — block AI crawlers, allow Google
Build a robots.txt visually. Allow Googlebot, block GPTBot/ClaudeBot/CCBot, set sitemap and crawl-delay. Copy ready-to-paste output for your domain root.
Free online slug generator — clean URL slugs from any title
Turn any title into a clean URL slug: lowercase, accents stripped, separator of your choice, max length capped. Runs in your browser, no upload.
Free online XML sitemap generator — sitemap.xml from URL list
Paste your site's URL list, set change-frequency and priority, get a valid sitemap.xml ready to upload. Sitemaps Protocol 0.9 compliant. Runs in your browser.
Diseño (7)
Conversor de colores online — HEX, RGB, HSL, HSV
Convierte cualquier color al instante entre HEX, RGB, HSL y HSV. Vista previa en vivo, selector nativo, copia con un clic. 100% en el navegador, sin subida.
Conversor de formato de imagen online gratis — JPG, PNG, WEBP
Convierte entre JPG, PNG y WEBP en tu navegador. Sin subida, sin seguimiento — la imagen se queda en tu dispositivo. Calidad ajustable, descarga instantánea.
Free online color palette generator — harmony schemes from any base
Generate harmonious colour palettes from any base hex: analogous, complementary, triadic, tetradic, monochromatic, shades. Copy as hex or HSL.
Free online CSS border-radius generator — independent corners
Design rounded shapes with independent control of all four corners, in pixels or percent. Live preview, ready-to-paste CSS. No sign-up.
Free online CSS box-shadow generator — multi-layer, inset, presets
Design CSS box-shadows with up to four stacked layers, live preview and ready-to-paste rule. Inset, presets, custom colors. No upload, no sign-up.
Free online CSS gradient generator — linear and radial
Design linear and radial CSS gradients with up to six colour stops. Live preview, ready-to-paste CSS, presets included. No sign-up, no upload.
Free online WCAG contrast checker — AA & AAA pass/fail
Compare two colours, see the WCAG contrast ratio and AA/AAA pass/fail for normal and large text. Live preview, ready for accessibility audits.
Calculadoras (7)
Free online BMI calculator — metric and imperial units
Compute your Body Mass Index instantly in metric (kg/cm) or imperial (lb/ft·in). WHO category, healthy weight range. Runs in your browser, no tracking.
Free online IPv4 CIDR calculator — subnet, mask, hosts, RFC 1918
Paste any IPv4/CIDR (192.168.1.0/24) and instantly see network, broadcast, mask, wildcard, host range, total and usable hosts, plus private/public detection.
Free online loan calculator — monthly payment and amortisation
Compute monthly payment, total interest and full amortisation schedule for any fixed-rate loan. Mortgage, car, personal. Multi-currency, in your browser.
Free online mortgage calculator — payment, taxes and insurance
Compute the full monthly mortgage payment: principal + interest + property tax + home insurance. Down payment slider, multi-currency. Runs in your browser.
Free online number base converter — binary, octal, decimal, hex, any base 2-36
Convert numbers between binary, octal, decimal, hex and any custom base from 2 to 36. BigInt-powered for huge numbers. Runs entirely in your browser.
Free online tip calculator — split bill across people, multi-currency
Calculate restaurant tip and split the total across any number of people. Tip presets (10-25%), custom percentage, multi-currency. Runs in your browser.
Free online unit converter — length, weight, temperature, more
Convert between metric and imperial units across 7 categories: length, weight, area, volume, speed, time, temperature. Live conversion in your browser.
Azar y decisiones (5)
Free online coin flip — heads or tails, animated, fair RNG
Flip a coin online — animated heads or tails, exact 50/50 fairness using cryptographic randomness. Batch flip 10 or 100 with running statistics.
Free online dice roller — d4 d6 d8 d10 d12 d20 d100 with modifier
Roll any tabletop dice in your browser: d4 to d100, multiple dice at once, optional modifier. Cryptographically secure, fair distribution. Roll history.
Free online list shuffler — randomise any list, pick subset, dedupe
Paste any list, get it randomly reordered with Fisher-Yates and a cryptographic RNG. Optionally dedupe and pick a random subset of N items.
Free online random number generator — secure, unbiased, batchable
Generate random integers in any range, single or in batches up to 1000, optionally unique. Cryptographically secure (Web Crypto API). Runs in your browser.
Generador de contraseñas online gratis — fuerte, aleatorio, seguro
Genera contraseñas aleatorias criptográficamente fuertes. Personaliza longitud y clases de caracteres. 100% en tu navegador, nunca transmitido, nunca almacenado.
Productividad (5)
Free online countdown timer — to any date and time
Live countdown to any future date and time. Days, hours, minutes, seconds. Custom event label. Runs entirely in your browser, no sign-up.
Free online NATO phonetic alphabet converter — Alfa Bravo Charlie
Convert any text or word into the NATO phonetic alphabet (Alfa, Bravo, Charlie…). Useful for radio communication, support tickets, spelling on the phone.
Free online Pomodoro timer — 25/5 focus and break cycles
Run Pomodoro focus sessions in your browser: 25-minute focus, 5-minute breaks, 15-minute long break every 4 sessions. Audio cue at end of each phase.
Free online word counter — words, characters, reading time
Count words, characters (with and without spaces), sentences, paragraphs, lines plus reading and speaking time, live as you type. No upload, no tracking.
Generador de Lorem Ipsum online gratis — párrafos, oraciones, palabras
Genera texto placeholder Lorem Ipsum. Elige párrafos, oraciones o palabras. Opcional «empezar con Lorem ipsum». Copia con un clic. 100% en el navegador.
Texto y datos (5)
Free online cron expression builder — schedule, parse, preview
Build cron expressions visually, see human-readable description and the next 5 fire times. 5-field POSIX format. Runs entirely in your browser.
Free online email validator — syntax check, typo fix, dedupe
Paste a list of email addresses, see which are syntactically valid, get suggested fixes for common domain typos (gmial.com → gmail.com), dedupe. No upload.
Free online Markdown table generator — visual editor
Build Markdown tables visually: edit cells in a grid, choose alignment per column, add/remove rows and columns. Copy GFM-compatible output. No upload.
Free online text case converter — camelCase, snake_case, kebab-case, more
Convert text between 12 cases: UPPER, lower, Title, Sentence, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, path/case, iNVERSE.
Generador de códigos QR online gratis — texto, URL, colores personalizados
Genera un código QR para cualquier texto o URL. Personaliza tamaño, colores y corrección de errores. Descarga como PNG. 100% en el navegador, sin subida, sin cuenta.