Check the execution label.
55 tool forms use the browser engine. Other forms send input to the server. Network lookups and device features may need a connection or browser permission; start with sample data.
145 free tools · 13 categories · no account
Free tools for developers, writers and AI agents: format JSON, clean pasted text, check colour contrast and more. Try a tool without an account. Each page labels whether its form runs in your browser or sends input to the server; the JSON manifest lists programmatic options.
55 tool forms use the browser engine. Other forms send input to the server. Network lookups and device features may need a connection or browser permission; start with sample data.
Where a tool has a client module, its manifest entry links to the JavaScript and exported function. Read the source and input schema before connecting it to an agent.
Open a tool to see its input fields, results and API example. The public manifest helps an agent find tools; it does not remove the need to check the output.
Search by the job you need to do, then check the execution label and input fields. Open a tool to try it and see its available API or module.
No tool matches that. Try a broader word — or browse the blog.
Enter confusion matrix values to calculate accuracy, precision, recall, F1
Cluster N-dimensional CSV data with K-Means++ and silhouette scoring
Paste 2D CSV data and visualize K-Means clustering
Fit OLS multivariate linear regression with R-squared and correlations
Fit a linear regression to 2D data with visualization
Train a Multinomial Naive Bayes text classifier and predict
Draw and paint with an intelligent color palette
Test text/background pairs against WCAG AA and AAA
Extract dominant colors from any uploaded image
Upload an image and click any pixel to get exact color values
View RGB color histograms and luminance distribution for images
Generate unique organic blob shapes as SVG paths
Strip editor metadata from SVG, reducing file size
Encode any file to Base64 data URI or decode back
Convert colors between HEX, RGB, HSL, and CSS named colors with live preview
Parse cron expressions into human-readable schedules and build cron syntax
Profile CSV columns: types, nulls, distributions, outliers
Auto-detect comma, tab, semicolon, or pipe delimiters
Convert CSV rows into flat JSON arrays or objects
Convert multiple Unix timestamps to human-readable dates
Encode images to Base64 strings for embedding in code
Validate ES6+ JavaScript syntax without execution
Format, validate, and syntax-highlight JSON data
Sort JSON object keys alphabetically for consistent diffs
Validate, pretty-print, or minify JSON strings
Build Open Graph tags for link previews on social media
Test regex patterns with token-by-token explanations
Find trends and anomalies in time-series sensor CSVs
Encode and decode URLs, parse query parameters, decompose URL components
Generate v1/v4/v7 UUIDs and validate existing ones
See your browser user agent string and parsed details
Reduce image file size while keeping quality
Convert between JPG, PNG, and WebP formats with quality control
Resize images to exact pixel dimensions
Paste SVG markup and download it as a PNG at any resolution
Turn plain text into a downloadable PDF
Convert between TXT and DOCX without uploading anywhere
Calculate numerical derivatives and definite integrals
Visualize Fourier series approximation of common waveforms
Perform matrix operations: multiply, transpose, determinant, inverse
Determinant, inverse, transpose, eigenvalues, LU decomposition, rank
Compute 1st-3rd derivatives numerically and find critical points
Definite integrals via Simpson's, trapezoidal, and Gaussian quadrature
Run Z-test, T-test, and chi-square hypothesis tests
Taylor series coefficients and polynomial comparison
Upload an audio file and visualize its frequency spectrum
Parse WAV audio: sample rate, channels, peak/RMS amplitude
Upload an animated GIF and extract individual frames as PNG
Analyse image dimensions, colors, brightness, and palette
Apply reverb, pitch shift, and EQ to MP3 files in-browser
Trim and cut MP3 audio clips without re-encoding
Generate tones from neural network computations on Pi
Convert text to audible Morse code, download as MP3
Detect video container format from file header bytes
Check if your title fits YouTube display limits
Analyze electric circuits: Ohm's law, series/parallel resistance
Analyze series and parallel circuits using Ohm's law
Coulomb's law, Biot-Savart, and RLC circuit impedance analysis
Explore the ideal gas law PV=nRT with interactive controls
Circular orbits, escape velocity, Hohmann transfers, and Kepler ellipses
Calculate simple and compound pendulum physics with animation
Simulate a pendulum wave with adjustable length and gravity
Simulate 2D projectile motion with adjustable angle and velocity
Ideal gas law, Carnot efficiency, heat transfer, and entropy
Superpose multiple waves, compute beat frequency and harmonics
Visualize two-wave interference patterns with adjustable parameters
Visualize wave interference and superposition of sine waves
Check if your browser canvas is used for tracking
Reveal your AudioContext fingerprint signature
See which installed fonts can identify your browser
Inspect and strip EXIF metadata before sharing photos
Strip metadata and redact sensitive text from documents
Check llms.txt, semantic HTML, and AI-bot rules for LLM discoverability
Analyze canonical URL declarations for SEO compliance
TF-IDF keyword extraction and SEO content gap detection
Analyze keyword density for SEO content optimization
Generate llms.txt and ai.txt files for AI crawler indexing
Analyze title, description, Open Graph, and Twitter Card tags
Validate Open Graph and Twitter Card meta tags
Full on-page SEO audit: title, meta, headings, images, links, structured data
Parse and validate robots.txt with crawl budget analysis
Test whether a URL is allowed or blocked by robots.txt rules
Validate JSON-LD structured data for SEO and rich results
Validate XML sitemaps: URL count, lastmod coverage, structural errors
Scan PHP, JS, or Python for SQLi, XSS, command injection, and weak crypto
Shannon entropy per byte and high-entropy blob detection
Paste a hash string to identify its type: MD5, SHA-1, SHA-256, bcrypt
Score HTTP security headers against OWASP best practices
Decode JWT tokens to inspect header, payload, and expiry
Generate strong multi-word passphrases with entropy estimates
Create random passwords with configurable length and rules
Comprehensive password strength analysis with entropy calculation
Audit password strength with entropy and crack-time estimates
Check HTTP security headers for websites
Scan code for common vulnerability patterns
See what your GPU and WebGL stack reveal to websites
Check what your WebGPU adapter and GPU reveal to sites
Extract, test, and visualize regex matches with named groups
Encode and decode text as Base64, URL-safe Base64, or Hex
Run multiple find-and-replace rules on text in a single pass
Format references in APA, MLA, Chicago, or BibTeX
Remove hidden formatting from AI-generated or pasted text
Format text with Discord-flavored Markdown syntax
Find and remove duplicate lines from any text block
Check subject line length for Gmail, Outlook, and mobile
Extractive TF-IDF summarization of long text
Detect language and estimate reading difficulty level
Generate custom-length lorem ipsum placeholder text
Write Markdown and see rendered HTML in real time
Extract emails, URLs, dates, phone numbers, hashtags, and IPs from text
Auto-detect and highlight emails, URLs, dates, phones, and IPs in text
Score and rewrite LLM prompts for clarity and specificity
Verify your Reddit title fits the 300-char limit
Find and strip zero-width and invisible Unicode chars
Audit plain-text resume formatting for ATS parsers
Write LaTeX math with live-rendered preview
Fix spacing, punctuation, and readability issues in text
Extract key-value pairs, lists, tables, emails, and URLs from text
Split long text into overlapping chunks for RAG pipelines
Apply colors to text and export as HTML or CSS
Word-level diff between two texts with highlighting and statistics
Compare two texts side-by-side with inline change highlighting
Write and edit plain text in a distraction-free editor
Calculate Shannon entropy and character frequency for text analysis
Compare two texts and get a similarity percentage
Fill Mustache-style templates with JSON data for bulk text generation
Convert any text to URL slugs or various case formats
Extract key sentences using TF-IDF scoring for text summarization
Lexicon-based sentiment and tone analysis
Count characters with t.co link shortening applied
Preview bold, italic, and mono formatting for WhatsApp
Strip trailing spaces, extra blank lines, and tabs
Count words, characters, sentences, and paragraphs instantly
Measure keystroke timing and typing rhythm patterns
Generate QR codes from text, URLs, or contact info
Predict scan reliability based on size and contrast
Visualize ideas as interactive mindmaps in your browser
Find shared work hours across 2 to 4 time zones
See your latitude, longitude, and accuracy from your browser
View your public IP address and basic connection info
Check connection type, downlink speed, and data saver
View screen resolution, viewport, and device pixel ratio
See your timezone, UTC offset, and DST status
How it works
Open a tool and test it with a small, non-sensitive input. For automation, use the page’s API example or a client module when its manifest entry provides one. Neither requires a site account or API key.
Search the directory, or fetch the manifest to inspect available tools and execution modes.
Read the tool’s fields and schema. Browser APIs such as Canvas and Web Crypto need a compatible runtime.
Use the form, server endpoint or documented module. Server calls send the supplied input over the network.
Check the output before using it. Large files, unsupported browser features and server limits can prevent a run.
For AI agents
The Word & Character Counter has a client module. This example finds that specific tool and counts a sample string in a browser runtime. Other entries may provide a server API instead.
// 1. Discover available tools const manifest = await fetch("https://itsfullyonline.yunusemrevurgun.com/api/manifest.json") .then(r => r.json()); // 2. Pick one and load it as an ES module const tool = manifest.categories.flatMap(c => c.tools) .find(t => t.apiName === "word-char-counter"); const mod = await import(`https://itsfullyonline.yunusemrevurgun.com${tool.clientModule}`); // 3. Execute with your input const result = await mod[tool.execFunction]({ text: " Hello " }); // This module counts the sample locally; fetching files uses the network.
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