Free tools

Free Online Web Tools for Everyone

Free online web tools by MACM. No ads, no sign-up, everything runs in the browser.

Dev Tools

64

CSV ↔ JSON Converter

Convert CSV to JSON and JSON to CSV both ways. 100% in your browser, no uploads.

SQL Formatter

Format and beautify SQL: MySQL, PostgreSQL, SQLite, SQL Server, BigQuery. 100% in your browser.

Code Minifier

Minify HTML, CSS and JavaScript removing comments and whitespace. 100% in your browser.

Certificate Decoder

Decode x.509 SSL/TLS certificates (PEM): issuer, validity, SAN, SHA-256 fingerprint. 100% in your browser.

Steganography (Hide Text)

Hide and reveal secret messages inside an image (LSB). 100% in your browser, PNG download.

JSON Formatter

Format, validate and minify JSON. Errors with exact line, tree view, sort keys. No sign-up.

Base64 Encoder

Encode and decode Base64 instantly. Full Unicode support, URL-safe mode. No sign-up.

URL Encoder

Encode and decode URLs with encodeURIComponent or encodeURI. Percent-encoding instantly. No sign-up.

Hash Generator

Generate MD5, SHA-1, SHA-256 and SHA-512 hashes in real time. Integrity verification. No sign-up.

Timestamp Converter

Convert Unix timestamps to readable dates. Live current timestamp. ISO 8601, UTC, relative. No sign-up.

UUID Generator

Generate unique UUID v4 with crypto.randomUUID(). Bulk generation, history, copy. No sign-up.

Number Base Converter

Convert between binary, octal, decimal and hex in real time. All fields update simultaneously.

JWT Decoder

Decode JWT instantly. Header, payload, standard claims and expiry verification. No sign-up.

HTTP Status Codes

Complete reference for 60+ HTTP 1xx-5xx status codes with bilingual descriptions and real-time search.

AES Text Encryptor

Encrypt text and files with AES-256-GCM and PBKDF2. 100% in browser. Data never leaves your device.

Regex Tester

Test regular expressions in real time. Match highlighting, capture groups and quick pattern reference.

Cron Builder

Build cron expressions visually. Natural language description and next 5 executions calculated.

SVG Optimizer

Clean and compress SVGs. Removes Inkscape metadata, empty groups and editor code. No external dependencies.

HTTP Headers Checker

Analyze HTTP headers of any URL. Status code, response time and security headers analysis: HSTS, CSP, X-Frame-Options.

IP Lookup

Discover your public IP or look up any IP. Country, city, ISP, timezone and coordinates in real time.

Web Analyzer

Full technical audit: DNS, WHOIS, SSL, SEO, email, redirects and stack. Score 0-100.

DNS Lookup

Query DNS records: A, AAAA, MX, TXT, NS, CNAME, SOA. Real time via Cloudflare.

WHOIS Lookup

Domain registration info: registrar, dates, nameservers. RDAP data.

SSL Checker

Verify SSL/TLS certificates: issuer, expiry, SANs, protocol and grade A+→F.

Redirect Checker

Trace URL redirect chain. HTTP code, URL and time per hop. Up to 10 hops.

Subdomain Finder

Discover subdomains via Certificate Transparency (crt.sh). Passive, no active scanning.

Email Security (SPF·DKIM·DMARC)

Verify SPF, DKIM and DMARC. Protected/partial/unprotected verdict against spoofing.

Tech Stack Detector

Detect framework, CMS, CDN, server and analytics. Next.js, WordPress, Cloudflare and more.

SEO Analyzer

On-page SEO audit: 19 checks, score 0-100, quick wins. Title, meta, H1, OG, schema.

Tabs to Spaces Converter

Convert your code's indentation between tabs and spaces, configurable width.

.gitignore Generator

Combine technologies and editors to generate your .gitignore instantly.

LICENSE Generator

Generate your project's LICENSE file: MIT, Apache 2.0, GPL 3.0, BSD, ISC.

chmod Calculator

Convert Linux permissions between octal (755, 644) and symbolic (rwxr-xr-x) with visual checkboxes.

Multi-Base Encoder

Encode and decode in Base64, Base32, Base58, Base85, Hex, URL or HTML in a single tool.

robots.txt Generator

Generate your robots.txt with per-bot rules, sitemap and AI crawler blocking (GPTBot, ClaudeBot...).

Dockerfile Generator

Optimized Dockerfiles for Node, Next.js, Python, Go and Rust with multi-stage and non-root user.

Docker Compose Generator

Build your local stack visually: PostgreSQL, MySQL, Redis, MongoDB, Nginx and your app in YAML.

Nginx Config Generator

Server blocks for static, SPA or reverse proxy with SSL, gzip, cache and security headers.

GitHub Actions Generator

Ready-to-go CI/CD workflows: Node CI, Vercel deploy or Docker image to GHCR with cache.

SSH Key Generator

Ed25519/RSA pairs in OpenSSH format generated with Web Crypto. The private key never leaves your device.

Browser Fingerprint Test

Find out how identifiable your browser is: canvas, WebGL, fonts and audio. Local analysis.

TOTP Authenticator (2FA)

2FA codes from your secret or otpauth:// URI, RFC 6238 verified. No servers.

AES Step-by-Step Visualizer

AES-128 round by round: SubBytes, ShiftRows, MixColumns and key schedule, validated with FIPS-197.

JSON to YAML/TOML

Converts JSON to YAML and TOML with a round-trip verified emitter.

systemd Service Generator

Ready systemd unit files: auto-restart, safe user and boot startup.

Punycode Domain Checker

Detects homoglyph spoofed domains and decodes xn-- (RFC 3492 verified).

SSH Config Generator

Visual ~/.ssh/config: aliases, per-host keys and ProxyJump hops without long commands.

RSA Step-by-Step Visualizer

Generate RSA keys and encrypt a message step by step: φ(n), extended Euclid and binary exponentiation, verified against OpenSSL.

CSV to SQL INSERT Converter

CSV to INSERT statements for MySQL, PostgreSQL, SQLite, SQL Server or ANSI, with an RFC 4180 parser and inferred CREATE TABLE.

CSV to ASCII Table Converter

CSV to aligned ASCII tables: Unicode boxes, plain ASCII or GitHub-ready Markdown, with automatic widths.

Phishing URL Checker

Analyze a suspicious link before clicking: typosquatting, homoglyphs, punycode, risky TLDs and subdomain tricks.

CSV Merger and Join

Stack several CSVs with unified headers or join them by column with INNER, LEFT, RIGHT and FULL JOIN.

Image to Base64

Convert an image to Base64 or a data URI and decode Base64 back to an image. With size, overhead and format detection.

Unicode Character Inspector

Code point, UTF-8, UTF-16, HTML entity, JavaScript and CSS escape and URL encoding of each character.

JSON Diff

Compare two JSON documents by structure, align arrays by key, ignore paths and export the differences as JSON Patch.

JSON to TypeScript and Zod

Generate TypeScript interfaces or types and Zod schemas from JSON, with optionals, formats and nested types.

JSON Schema Generator

Create a JSON Schema 2020-12 or draft-07 from examples and validate documents against it with errors by path.

cURL to Code

Convert cURL commands to fetch, axios, Python, Go, PHP, Rust, Java and C#, moving tokens to environment variables.

URL Parser and Cleaner

Break a URL into parts, edit parameters, strip tracking (utm, fbclid) and unwrap redirect links.

HTML Entities Encoder and Decoder

Encode and decode HTML entities with all 2,125 from the standard, detect invisible characters and double encoding.

HTML Formatter

Beautify and minify HTML while preserving inline whitespace, pre, script and style, with warnings for unclosed tags.

Meta Tags Generator

Create meta tags, Open Graph and Twitter Cards with previews for Google, WhatsApp, X, Discord and Slack, and export to Next.js.

SemVer Calculator

Check npm, Cargo and Composer ranges, compare and sort versions and compute the next major, minor or patch.

XML Formatter and Validator

Beautify, minify and validate XML with errors by line, convert to JSON and test XPath expressions.

CSS & Design

14

Color Palette Generator

Generate harmonic palettes: complementary, analogous, triadic and shades. Copy any HEX.

CSS Unit Converter

Convert px, rem, em, vw, vh, pt in real time. Configurable base font-size and viewport.

CSS Gradient Generator

Create linear, radial and conic CSS gradients. Real-time preview, presets and CSS code ready to copy.

CSS Box Shadow Generator

Create CSS shadows with multiple layers. Offset, blur, spread, color, opacity and inset per layer. Live preview.

Glassmorphism Generator

Frosted-glass effect with adjustable blur and transparency, live preview and ready-to-paste CSS.

Neumorphism Generator

Soft UI styles with dual shadow (raised/pressed), adjustable light angle and intensity.

Clip Path Maker

Crop elements with preset shapes or draggable vertices: polygon, circle and ellipse.

CSS Loader Generator

Animated spinners in pure CSS: rings, dots, bars, pulse and ripple. No JavaScript or GIFs.

Border Radius Generator

Per-corner rounded shapes or organic blobs with the 8-value syntax.

CSS Triangle Generator

Triangles and arrows with the border trick: 8 directions, size and color.

CSS Toggle Switch Generator

Animated pure-CSS switches with accessible checkbox. No JavaScript.

Custom Scrollbar Generator

Styled scrollbars for Chrome, Safari and Firefox with a live preview.

Flexbox Generator

Build flex layouts visually, tweak each item and copy the CSS, the HTML or the Tailwind classes.

CSS Grid Generator

Draw grid areas by dragging, define columns and rows and export responsive CSS or Tailwind.

Images

17

Image Converter

Convert PNG, JPG, WebP, AVIF, BMP and ICO. Generate favicons with multiple resolutions. No sign-up.

Photo Editor

Filters, adjustments, crop and rotation. B&W, Sepia, Vintage and more. No sign-up.

Background Remover

Remove the background from any photo with AI, 100% in your browser. No uploads, no watermark. Transparent, color or image background.

Image Compressor

Compress JPG, PNG and WebP in batch with quality control. Download as ZIP. 100% in your browser.

Image Resizer

Resize images in batch by percentage or max dimension. Download as ZIP. 100% in your browser.

Video Editor

Trim, compress, convert and edit videos. Rotate, GIF, watermark, subtitles. No sign-up.

Metadata Analyzer

Analyze, remove and edit EXIF, GPS, IPTC and XMP metadata. Lossless for JPEG. Privacy risk indicator. No sign-up.

Favicon Generator

Create favicons from image or text/emoji. 8 sizes (16px to 512px), Apple Touch Icon, PWA and HTML snippet. No sign-up.

Image Map Generator

Create clickable zones on images. Rect, circle and poly. Undo/redo, snap to grid, zoom. Export HTML or JSON.

AI Image Upscaler

Upscale photos ×2/×4 with Swin2SR on your GPU. Before/after slider, no uploads.

Image Color Palette Extractor

Extract the dominant colors from any image with k-means, in your browser. HEX, RGB, HSL and CSS export.

BlurHash Placeholder Generator

LQIP BlurHash placeholder from any image, with decoded preview and HTML, CSS and React snippets.

Duplicate Image Finder

Find duplicate photos with pHash, aHash and dHash by dropping whole folders. 100% local.

Image Comparison Slider

Compare two images with a before/after slider and generate the HTML code with embedded images.

Color Blindness Simulator

Simulate protanopia, deuteranopia, tritanopia and achromatopsia on a color or an image. With ΔE distance.

Image Watermark

Add text or a logo as a watermark, tiled or freely placed, and process batches of photos into a ZIP.

Passport Photo Maker

Crop your photo for a passport, ID or visa with the head at the official size and create a sheet to print.

Audio

23

Audio Cutter

Trim MP3, WAV, OGG, FLAC or M4A by exact seconds. Fast mode with no re-encode. 100% in your browser.

Audio Converter

Convert between MP3, WAV, OGG, FLAC, M4A and Opus with bitrate control. 100% in your browser.

Text to Speech

Listen to any text with your system's voices. Adjustable rate, pitch and volume. No server.

Audio to Text (AI)

Transcribe any audio to text with AI (Whisper), 100% in your browser. No minute limits.

Audio Normalizer

Adjust volume to the podcast, music or broadcast (EBU R128) LUFS standard. 100% in your browser.

Merge Audio Files

Combine several audio files into one, in the order you choose. Mix different formats. 100% in your browser.

Audio Fade In/Out

Add a fade in and fade out to your audio, with adjustable duration. 100% in your browser.

Silence Remover

Automatically remove silence from an audio file, with adjustable threshold and duration. 100% in your browser.

Tone Generator

Generate pure tones at any frequency and waveform, listen or download as WAV.

Online Metronome

Metronome from 30 to 300 BPM, adjustable time signatures and tap tempo. 100% in your browser.

Audio Spectrum

Visualize the frequencies or waveform of an audio file or your microphone in real time.

Audio Recorder

Record with your microphone, pause and resume, download instantly. 100% in your browser.

Ringtone Maker

Turn any song into a short ringtone with a smooth fade. 100% in your browser.

Audio Beep Generator

Censor words or sections of an audio with a beep, with exact control over start and end.

Audio Speed and Pitch

Change speed while keeping pitch, or pitch while keeping speed, from 0.25x to 4x.

Retro SFX Generator

Generate 8-bit sound effects (coin, jump, laser, explosion...) with random variations.

Guitar Tuner

Tune your guitar with your microphone and real-time note and cents detection.

Audio Noise Reducer

Reduce constant background noise from a recording with a spectral denoiser. 100% in your browser.

ID3 Tag Editor

Edit title, artist, album, year, genre and cover art of your MP3s. 100% in your browser.

Audio Stem Separator (AI)

Split a song into vocals, drums, bass and other instruments with AI (HTDemucs). 100% in your browser.

Speaker Test

Test L/R channels, phase and a 20 Hz to 20 kHz sweep.

A/B Audio Comparator

Switch between two audio tracks instantly with crossfade and RMS-matched levels.

Tap BPM Meter

Find a song's BPM by tapping the beat, with statistical median and spread.

PDF

18

Document Scanner

Scan documents with your camera, fix the perspective, apply filters and export to PDF. Multi-page and OCR. 100% in your browser.

Rotate PDF

Rotate PDF pages 90, 180 or 270 degrees. 100% in your browser, no watermark.

Reorder PDF Pages

Change the order of PDF pages. 100% in your browser, no watermark.

PDF to Text

Extract all the text from a PDF and download it as .txt. 100% in your browser.

Add Page Numbers to PDF

Add page numbers to a PDF, configurable position and start number. 100% in your browser.

PDF Tools

Hub of 6 PDF tools: images to PDF, merge, split, PDF to images, compress and watermark.

Images to PDF

Convert JPG, PNG, WebP and more to PDF. Drag & drop to reorder, A4/Letter size, margins. No sign-up.

PDF Merge

Merge multiple PDFs into one. Reorder with drag & drop. No sign-up, 100% in browser.

PDF Split

Split a PDF by page range, every N pages or page by page. No sign-up.

PDF to Images

Convert each PDF page to JPG or PNG. 1x, 2x or 3x resolution. No sign-up.

PDF Compress

Reduce PDF size by removing metadata and optimizing structure. No quality loss.

PDF Watermark

Add text watermark to all PDF pages. Configurable position, opacity and color.

PDF Remove Pages

Visually select pages to delete from a PDF and download the result. No sign-up.

Spanish Invoice Generator

Invoices with Spanish legal fields, VAT, IRPF, validated NIF and total in words.

Spanish Quote Generator

Quotes with PRE numbering, validity with expiry, per-item VAT and total in words.

Spanish Delivery Note Generator

Delivery notes with ALB numbering, validated NIF and receipt signatures.

PDF Metadata Editor

View, edit and remove PDF metadata, including hidden XMP, and clean several files at once.

Sign PDF

Sign a PDF by drawing, typing or with a photo of your signature, add a date or text and place them on any page.

Text

12

Education

3

Utilities

35

QR Code Generator

Generate QR for URLs, text and contacts. Add your logo. Download as PNG. No sign-up.

Password Generator

Generate secure passwords and passphrases. Real entropy, no servers, no history.

Color Converter

Convert between HEX, RGB, HSL and HSV. Palettes, related colours and WCAG contrast.

Complete Calculator

Scientific, programmer and financial. Binary/hex/octal, bitwise ops, mortgages and compound interest.

Aspect Ratio Calculator

Calculate width and height keeping the ratio (16:9, 4:3, 21:9…). Simplified ratio.

Unit Converter

Convert length, weight, temperature, area, volume, speed, digital storage, time and pressure. Over 80 units.

Pomodoro Timer

Pomodoro timer with browser notifications, sound, session statistics and customizable durations.

Diceware Passphrase Generator

Generate secure, memorable passphrases by combining random words with crypto.getRandomValues.

Password Entropy Calculator

Measure a password's real strength in bits, detect common patterns. Never leaves the browser.

File Hash Checker

Calculate the SHA hash of any file and compare it with a known one to verify its integrity.

Random List Picker

Pick a random winner with real cryptographic randomness, give out several prizes without repeats.

Password Strength Checker

Analyze passwords with zxcvbn (Dropbox): score, crack time and concrete warnings. 100% local.

ZIP Encryptor with AES-256

Password-protect files and folders in an AES-256 ZIP, and open protected ZIPs in your browser. 100% local.

Online Screen Recorder

Record screen, window or tab in 4K/1080p with system audio and mic — no watermark, no install.

Camera and Microphone Test

Test camera and mic: live preview, real resolutions, level meter and L/R speaker test.

Screen Color Picker

Grab any screen pixel with the native picker: HEX, RGB, HSL, WCAG contrast and an exportable palette.

Keyboard Tester

Test every key with a visual map and measure anti-ghosting with simultaneous presses. 100% local.

Screen Test

Find dead pixels, stuck pixels and backlight bleed with a fullscreen color sweep.

Wheel of Names

Random wheel for raffles and decisions with a cryptographically uniform winner, history and remove-winner mode.

WebRTC Leak Test

Check whether your browser reveals your real IP via WebRTC even with a VPN, with a copyable report.

Mouse Tester and CPS

Measure your click speed (CPS), double click and check mouse buttons and wheel.

Dice Roller

RPG dice with NdS notation and unbiased cryptographic randomness.

Coin Flipper

Coin flipper with cryptographic randomness and best-of-N series.

Random Team Generator

Split names into random balanced teams with cryptographic shuffling.

Reading Speed Test

Measure your words per minute with a timer, built-in texts and a comprehension quiz.

Barcode Generator

Scannable EAN-13 and Code 128 barcodes with SVG and PNG download.

Interval Timer

Tabata and HIIT with rounds, sets, countdown and phase-change beeps.

ICS Event Generator

RFC 5545 .ics events with reminders, recurrence and Google or Outlook links.

WiFi QR Generator

Share your WiFi with a standard QR that connects on scan, no password typing.

Age and Date Calculator

Exact age in years, months and days, date difference and business days with Spanish holidays.

DNI, NIE and CIF Validator

Check Spanish DNI, NIE and CIF and compute the check letter or digit with the official algorithm.

IBAN Validator

Validate IBAN with the mod 97 algorithm, identify the country, format the number and compute the check digits.

Time Zone Converter

Convert the time between any pair of IANA time zones, with daylight saving and the hour difference.

Percentage Calculator

Eight percentage calculations with step-by-step formulas: change, chained discounts, margin, markup and reverse percentage.

Spanish VAT (IVA) Calculator

Add or remove Spanish VAT, IGIC or IPSI, apply equivalence surcharge and IRPF withholding, with multiple lines and cent-exact maths.

Desktop

1

More tools coming soon.

What are these tools?

This section brings together free web utilities developed by Miguel Ángel Colorado Marin (MACM) to simplify everyday tasks for developers, designers and anyone working in digital environments. All tools run directly in the browser, with no installation or account required.

The code for each tool is available on GitHub under the MIT licence. If you find a bug or have a suggestion, you can open an issue or contact directly through the portfolio.

🔒

Full privacy

All processing happens in your browser without sending any data to external servers, ensuring complete privacy.

⚡

No sign-up

Access any tool directly without needing to create an account or provide your email address.

📖

Open source

Repositories are public on GitHub and you can freely inspect, modify and reuse the source code.

🛜

Works offline

Install the app as a PWA and use it without wifi. Tools you visit stay available without an internet connection.