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Utilidades rápidas y simples para convertir, calcular, formatear, generar y crear — directamente en tu navegador. Sin registro. Sin subidas. Sin seguimiento.
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Rápido y gratis
Sin registro, sin muros de pago, sin esperas. Las herramientas cargan al instante desde una red global.
Simple
Cada herramienta hace una sola cosa bien. Sin desorden, sin patrones oscuros, sin trampas de modales. Llegas, lo usas, te vas.
Herramientas populares
Las herramientas más usadas en Uttir. Haz clic en cualquiera para abrirla al instante.
JSON Formatter
Format, beautify, and validate JSON with adjustable indentation — instantly in your browser.
Developer Tools
UUID Generator
Generate cryptographically random UUID v4 identifiers, one or a thousand at a time.
Developer Tools
Base64 Encoder
Encode any text — including emoji and non-Latin scripts — into standard Base64.
Developer Tools
JWT Decoder
Decode a JWT’s header and payload and check its expiration — without sending it anywhere.
Developer Tools
JWT Sign (HS256 / RS256)
Sign a JSON Web Token with HS256 (HMAC shared secret) or RS256 (RSA private key). Output is a standard compact JWT (header.payload.signature).
Security Tools
HMAC Generator
Compute a Hash-based Message Authentication Code (HMAC) for any message and shared secret. Supports SHA-256, SHA-512, SHA-1, and MD5. All computation runs in your browser.
Security Tools
Regex Tester
Test and debug regular expressions with live matches, capture groups, and highlighted results.
Developer Tools
Word Counter
Count words, characters, sentences, and paragraphs in your text instantly.
Text Tools
Percentage Calculator
Three percentage tools in one: percent of a value, ratio as a percent, and percent change.
Calculators
Herramientas más nuevas
recién añadidasInternet Speed Test
Measure your download speed, latency, and jitter in the browser. Download-only: nothing is uploaded and nothing is tracked.
Network Tools
NewNetwork Latency Test
Ping several well-known endpoints from your browser and compare round-trip times to work out whether a slowdown is you or them.
Network Tools
NewClick Speed Test
Measure your clicks per second (CPS) over 1, 5, 10, or 30 seconds. Works with touch too, and keeps your personal best on this device.
Web Tools
Explorar por categoría
222 herramientas en 19 categorías. Elige una categoría para ver todo lo que contiene.
Developer Tools
Format, validate, decode, and generate the things developers deal with every day.
72 herramientas →Text Tools
Count, convert, compare, and clean up text instantly.
42 herramientas →Calculators
Quick, accurate calculators for percentages, dates, ages, and finance.
47 herramientas →Color Tools
Pick colors, convert formats, and check accessibility.
10 herramientas →Image Tools
Convert, compress, and resize images without uploading them.
25 herramientas →PDF Tools
Merge, split, and convert PDFs locally in your browser.
25 herramientas →Converters
Convert between formats, units, and standards.
19 herramientas →SEO Tools
Generate meta tags, sitemaps, robots.txt, and UTM links.
11 herramientas →File Tools
Work with files directly in your browser.
3 herramientas →Generators
Generate passwords, IDs, dummy data, and more.
26 herramientas →Date & Time Tools
Work with dates, times, durations, and time zones.
9 herramientas →Encoding Tools
Encode and decode Base64, URLs, HTML entities, and more.
12 herramientas →Data Tools
Transform CSV, JSON, XML, and YAML.
19 herramientas →Web Tools
Utilities for building and testing websites.
25 herramientas →Media Tools
Work with audio and video in your browser.
4 herramientas →Math Tools
Statistics, equations, sequences, and number theory.
18 herramientas →AI Tools
AI-powered utilities that run entirely in your browser.
5 herramientas →Desde el blog
What Is My IP Address — And What Does It Reveal About Me?
Your IP address is a public identifier that any website you visit can see. Learn what it exposes (city, ISP, ASN, sometimes a VPN), what it does not expose, and how to check yours without uploading anything.
31 ago 2026 · 7 min de lectura
How to Create an XML Sitemap (and Why You Need One)
A sitemap.xml file tells search engines which pages on your site exist. Learn what to include, what to leave out, how to write one by hand or generate one, and how to submit it to Google and Bing.
31 ago 2026 · 7 min de lectura
How to Test Color Contrast for Accessibility (WCAG 2.2 Explained)
Color contrast is the most-measured accessibility metric on the web. This guide explains the WCAG 2.2 contrast formula, the AA and AAA thresholds, and how to make sure your site is usable for people with low vision.
31 ago 2026 · 6 min de lectura
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