Tools Online Web

Choose from all available web tools. They are fast, free, and easy to use.

Developer Tools

A collection of highly useful tools, mainly for developers — and not only for them.

.gitignore Generator

Build your .gitignore from 312 official templates, including Bun, Tauri, Expo, NestJS and Cursor. It explains what each rule ignores and tests whether a path is excluded.

Barcode Generator

Create EAN-13, EAN-8, UPC-A, Code 128, Code 39, ITF-14 and Codabar barcodes. It works out the check digit for you and downloads as SVG or PNG. All in your browser.

Base64 Encoder and Decoder

Encode and decode text in Base64 with UTF-8 support and a URL-safe variant. Also convert files and images to Base64 or a Data URL. No sign-up.

CSS Beautifier

Format and unminify CSS, SCSS and Less with Prettier. Choose indentation and line width, then download the result. All in your browser, nothing uploaded.

cURL to Code Converter

Convert a cURL command into ready-to-copy code in PHP (Laravel and Guzzle), JavaScript (fetch), Node.js (axios), Python (requests) and Go. All in your browser.

Docker Compose Validator

Validate your compose.yaml against the official Compose schema and catch key typos, wrong types and YAML errors, with the exact line. All in your browser.

HEX, RGB and HSL Color Converter

Convert colors between HEX, RGB and HSL instantly. Includes a picker, alpha channels, a tints-and-shades palette and a WCAG contrast check.

HTML Beautifier

Format and indent HTML and Vue templates with Prettier, including embedded CSS and JavaScript. Choose indentation and line width. All in your browser.

HTML Minifier

Minify your HTML by removing all unnecessary characters.

848 views 69 uses

JavaScript Beautifier

Format and unminify JavaScript, TypeScript and JSX with Prettier. Control quotes, semicolons, indentation and line width. All in your browser.

JSON to TypeScript & Code Converter

Convert any JSON into TypeScript interfaces, Zod schemas, PHP classes, Python dataclasses or Go structs. Detects nested and optional types. All in your browser.

MD5 & SHA Hash Generator

Compute the MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of any text or file, with a checksum verifier. All in your browser, no sign-up.

Mexican ID Validator — RFC, CURP, CLABE, NSS

Check whether an RFC, CURP, CLABE or NSS is correct. Detects the type on its own, verifies the check digit and breaks down every part of the ID. All in your browser.

QR Code Generator

Create QR codes for URLs, WiFi, email, phone or SMS. Customize color, size and error correction, and download them as PNG or SVG. No watermarks.

Regex Tester

Test regular expressions in real time with match highlighting, capture groups, flags, $1 replacement and a quick reference. No sign-up.

Secure Password Generator

Create strong random passwords instantly. Adjust length, uppercase, numbers and symbols, with a live strength meter. Everything in your browser.

Unix Timestamp Converter

Convert Unix timestamps to a readable date (ISO, UTC, local and relative time) and dates back to a timestamp, with seconds/milliseconds detection and a live clock. No sign-up.

URL Encoder and Decoder

Encode and decode URLs and parameters instantly, with a component or full-URL variant. Includes a query string parser. No sign-up.

UUID Generator

Generate random v4 and time-ordered v7 UUIDs in bulk, with format options and download. Includes an inspector that detects version and variant. No sign-up.

Word and Character Counter

Count words, characters, sentences and paragraphs in real time, with reading time and keyword density. Ideal for SEO, essays and social media.

CSS Minifier

Minify your CSS by removing all unnecessary characters.

798 views 26 uses

JavaScript Minifier

Minify your JS by removing all unnecessary characters.

761 views 12 uses

JSON Validator and Beautifier

Validate, beautify and format JSON online for free. Instantly spot syntax errors, indent or minify your JSON and copy it with one click.

1,086 views 8 uses

SQL Formatter / Beautifier

Format and beautify your SQL code with ease.

1,125 views 24 uses

HTML Entity Converter

Encode or decode HTML entities for any given input.

971 views 14 uses

JWT Decoder and Verifier

Decode the header and payload of a JSON Web Token and verify its HS256/384/512 or RS256/384/512 signature.

AI & LLM

Tools for working with language models: count tokens, calculate costs and see how your text is split. Deterministic and in your browser, with no API calls.

LLM Token Counter & AI Cost Calculator

Count the tokens in your text or prompt and estimate the cost across GPT-5, Claude, Gemini, Kimi K3, Grok and DeepSeek. Exact OpenAI counting, per-call and monthly costs, with prompt caching.

Tokenizer Visualizer

Paste text and see exactly which tokens a language model splits it into, with their IDs. Check why Spanish costs more tokens than English.

Check Tools

A collection of great checker-style tools to help you validate and verify.

BIMI Checker

Check a domain's BIMI record, which shows your brand logo next to authenticated email in the inbox.

Blacklist Checker (DNSBL)

Check whether an IP or domain appears on email blocklists (DNSBL) that hurt the deliverability of your messages.

CAA Checker

Check a domain's CAA records to see which certificate authorities are allowed to issue its SSL certificates.

DKIM Checker

Look up a domain's DKIM public keys by selector. Provide your selectors or let common provider selectors be probed.

DMARC Checker

Look up and analyse a domain's DMARC record —policy (p=), reporting (rua), percentage and alignment— with actionable warnings.

DNS Lookup

Find A, AAAA, CNAME, MX, NS, TXT and SOA DNS records for a host.

1,203 views 173 uses

DNS Propagation Checker

Check a domain's DNS propagation by querying several resolvers worldwide and comparing their answers.

DNSSEC Checker

Check whether a domain is protected by DNSSEC, inspecting DS/DNSKEY records and validation of the chain of trust (AD flag).

Domain Health Report

Audit a whole domain in one query: DNS, SPF, DKIM, DMARC, DNSSEC, CAA, TLS certificate and security headers, with a prioritised list of what to fix.

Email Auth Checker (SPF, DKIM, DMARC)

Audit a domain's SPF, DKIM and DMARC records and get a graded report with fixes to stop email spoofing.

Email Header Analyzer

Analyze an email's headers in your browser and review the Received route with delays plus the SPF, DKIM and DMARC verdicts.

HTTP Security Headers

Analyse a site's HTTP security headers (HSTS, CSP, X-Frame-Options and more) and get a grade plus the ones you are missing.

MTA-STS Checker

Check a domain's MTA-STS policy (DNS record and .well-known file) that enforces TLS for inbound email.

MX Lookup

Look up a domain's mail servers (MX records), their priority and the IPs they resolve to.

SPF and DMARC Record Generator

Build your domain's SPF and DMARC records with a wizard: pick your email providers and get the TXT ready to publish, with warnings about the mistakes that break mail.

SPF Checker

Analyse a domain's SPF record, detect its trailing qualifier (-all, ~all) and count DNS lookups against the limit of 10 (RFC 7208).

Subnet Calculator

Work out network, broadcast, host range, netmask and wildcard from CIDR notation, for IPv4 and IPv6. Split a block into subnets. All in your browser.

TLS-RPT Checker

Check a domain's TLS-RPT record to see whether it receives reports about email TLS encryption failures.

WHOIS Lookup

Look up a domain's registration data (registrar, creation and expiry dates, name servers and status) straight over the WHOIS protocol.

IP Lookup

Get approximate details about an IP address.

831 views 116 uses

Reverse IP Lookup

Takes an IP address and finds the domain or host (PTR record) associated with it, with geolocation and provider. Free and no sign-up.

1,218 views 147 uses

SSL Lookup

Get all the details you can about an SSL certificate.

916 views 126 uses

Text & SEO

Text, content and SEO tools to write, optimize and publish faster.

Case Converter

Convert text to UPPERCASE, lowercase, Title Case, camelCase, snake_case, kebab-case and more instantly. Copy each format with one click. No sign-up.

Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text in paragraphs, sentences, words or lists, with optional HTML format. Copy or download instantly. No sign-up.

Slug / URL Generator

Turn any title into an SEO-friendly slug: strips accents and symbols, lowercases and joins with hyphens. Configurable separator and stop words. No sign-up.

Meta Tags & SERP Preview Generator

Build any page's meta tags (title, description, Open Graph and Twitter) with a Google-style result preview and length counters. No sign-up.

UTM Campaign URL Builder

Build links with UTM parameters (source, medium, campaign, term and content) to track your campaigns in Google Analytics. With suggestions and lowercasing. No sign-up.

Text Summarizer

Summarize long texts in seconds by picking the key sentences, right in your browser. Works in English and Spanish. Copy the result. Free and private.

Image

Compress, convert and edit images right in your browser, without uploading them to any server.

Favicon Generator

Create your site's favicon from an image or from text/emoji. Download the full pack (favicon.ico, PNGs, apple-touch-icon and site.webmanifest) with ready-to-use HTML. All in your browser.

Image Compressor

Compress and optimize JPG, PNG or WebP images without visible quality loss, with quality control, format change and resizing. All in your browser.

Image Converter

Convert images between WebP, JPG and PNG in batches, with quality control and individual or bulk download. All in your browser, nothing uploaded.

Image Resizer

Resize your images by pixels or percentage, keeping the aspect ratio, with format change and download. All in your browser, nothing uploaded.

Background Remover

Remove the background from any image with AI, right in your browser. Download a transparent PNG or swap the background for a color. Free and private.

Image to Text (OCR)

Extract text from an image or photo with OCR, right in your browser. Supports English, Spanish and more languages. Copy or download the result. Free and private.

Design & CSS

Visual CSS generators —gradients, shadows and effects— with live preview and ready-to-copy code.

CSS Gradient Generator

Create linear, radial and conic CSS gradients with live preview, unlimited color stops and ready-to-copy code. No sign-up.

CSS Box Shadow Generator

Create CSS box-shadow effects with offset, blur, spread, color and opacity control, multiple layers, inset and live preview. No sign-up.

CSS Glassmorphism Generator

Create the frosted-glass (glassmorphism) effect in CSS with blur, transparency, saturation, border and radius, with live preview. No sign-up.

Data & Format

Convert, compare and transform data between formats —JSON, CSV, YAML, Markdown and more— right in your browser.

CFDI 4.0 XML Viewer

Open a CFDI 4.0 invoice XML and read it in plain language: issuer, recipient, line items, taxes and tax stamp, with SAT codes translated and the arithmetic checked.

JSON and CSV Converter

Convert JSON to CSV and CSV to JSON instantly, with a configurable delimiter, type detection and download. All in your browser, nothing uploaded.

XML and JSON Converter

Convert XML to JSON and JSON to XML in both directions, with control over attributes and indentation. All in your browser, nothing uploaded.

XML Formatter and Validator

Indent, minify and validate XML in your browser. It preserves comments, CDATA and the declaration, and points at errors with line and column.

Text Diff Checker

Compare two texts and highlight the differences line by line, with unified and side-by-side views and ignore case or whitespace. All in your browser.

JSON and YAML Converter

Convert JSON to YAML and YAML to JSON instantly, with configurable indentation, download and copy. All in your browser, nothing uploaded.

Markdown and HTML Converter

Convert Markdown to HTML and HTML to Markdown instantly, with rendered preview, source code and download. All in your browser, nothing uploaded.

Number Base Converter

Convert numbers between binary, octal, decimal, hexadecimal and any base from 2 to 36 instantly, with arbitrary precision. All in your browser.

Utilities

Assorted calculators and generators for everyday work —dates, mock data and more— right in your browser.

Date and Age Calculator

Get your exact age in years, months and days, or the days between two dates. Add or subtract deadlines too. Free, no signup, instant.

Mexican Test Data Generator

Generate fictitious RFC, CURP, CLABE and NSS with correct check digits to seed development environments and tests. Export to JSON, CSV or SQL. No server involved.

Mock Data Generator

Generate realistic mock data (names, emails, dates, UUIDs, numbers and more) with a configurable schema and export to JSON or CSV. All in your browser.

Cron Expression Validator

Validate and explain cron expressions in plain language, with a field breakdown and the next runs. Supports ranges, lists, steps and shortcuts. No sign-up.

robots.txt Generator

Build your site's robots.txt with per-robot rules (Allow, Disallow, Crawl-delay) and sitemaps, with quick templates. Copy or download instantly.

Need a specific tool?

If you have a tool suggestion you would like to see here, feel free to contact me.