Free developer tools.

Count words, characters, sentences, and paragraphs.

Convert text to UPPER, lower, Title, camelCase, snake_case, and more.

Generate placeholder text in paragraphs, sentences, or words.

Compare two texts and see the differences highlighted.

Write Markdown and see the rendered HTML output in real time.

Convert titles and text into SEO-friendly URL slugs.

Estimate reading time, speaking time, word count, and character count for any text.

Remove duplicate lines from text while preserving order or sorting unique values.

Sort lines alphabetically, numerically, by length, ascending or descending.

Remove blank lines, whitespace-only lines, or compact text into a clean line list.

Normalize spaces, tabs, line breaks, and smart whitespace in pasted text.

Convert between HEX, RGB, HSL, and CMYK. Pick a color to start.

Generate color palettes from a base color. Shades, tints, and complements.

Build CSS gradients visually. Linear and radial. Copy the CSS.

Check foreground/background color contrast against WCAG AA and AAA text guidelines.

Build CSS box-shadow styles visually and copy the generated CSS.

Generate border-radius CSS with linked or independent corner controls.

Design a CSS button with colors, padding, radius, font weight, and hover styles.

Create frosted glass UI CSS with blur, opacity, border, and shadow controls.

Format, minify, and validate JSON. Catch errors instantly.

Encode text to Base64 or decode Base64 back to text.

Encode or decode URLs and query strings. Handle special characters.

Encode or decode HTML entities. Prevent XSS, display special characters.

Test regular expressions with real-time matching and highlighting.

Decode JSON Web Tokens to inspect header, payload, and signature.

Query JSON with simple dot/bracket paths and preview the extracted value.

Escape or unescape strings for JSON, JavaScript, HTML, URLs, and regex.

Convert simple YAML into pretty-printed JSON in your browser.

Convert JSON objects and arrays into readable YAML.

Format and lightly validate TOML-style config files.

Format XML with indentation and basic parse-error detection.

Convert tab-separated values into properly quoted CSV.

Format SQL queries with readable line breaks and indentation.

Format GraphQL queries, mutations, fragments, and selection sets.

Format HTML markup with indentation for nested tags.

Format CSS rules, declarations, media queries, and nested blocks.

Validate JSON data against a practical subset of JSON Schema.

Calculate the exact duration between two dates and times.

Quickly calculate tip amount and total bill.

Calculate sale price and savings from a discount percentage.

Convert between Bytes, KB, MB, GB, and TB instantly.

Estimate download/upload time based on file size and speed.

Generate realistic first + last name combinations.

Generate brandable .com domain name ideas from keywords.

Generate SEO-friendly meta descriptions from a page title and topic.

Generate common open source license text (MIT, Apache 2.0, GPL-3.0, BSD).

Generate a clean, professional README.md template for your project.

Check password strength and get improvement suggestions.

Generate regex patterns from positive and negative examples.

Generate structured data markup for Article, Product, FAQ, and Organization.

Improve clarity, structure, and effectiveness of AI prompts.

Check domain SSL certificate details and get guidance.

Send test requests to webhook URLs and view responses.

Extract dominant colors from an image.

Analyze word frequency and keyword density in text.

Decode and inspect JSON Web Tokens.

Look up A, AAAA, MX, TXT, and CNAME records for a domain.

Preview and generate rename commands for multiple files.

Generate high-quality few-shot examples for AI prompts.

Validate OpenAI and Anthropic function calling JSON structure.

Quick self-audit checklist for LCP, FID, and CLS.

Simplify and clean SVG path data.

Project how long your savings will last with different withdrawal rates.

Estimate capital gains on crypto trades using FIFO method.

Simulate different chunk sizes for RAG systems.

Find internal linking opportunities in your content.

Analyze logs for errors, warnings, and patterns.

Validate .env files for required variables and format.

Generate simple mock JSON responses for API endpoints.

Simulate multi-turn conversations with an AI agent.

Generate BlurHash placeholders from images.

Generate evaluation rubrics and sample datasets for LLM testing.

Convert length, weight, temperature, volume, and more.

Convert Unix timestamps to human-readable dates and vice versa.

Convert between binary, octal, decimal, and hexadecimal.

Paste CSV data and convert it to a JSON array instantly.

Convert a JSON array of objects into downloadable CSV.

Convert CSV data into a clean Markdown table.

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text.

Generate UUID v4 tokens. One or many at once.

Generate strong random passwords with custom length and character sets.

Generate unique usernames with styles, keywords, numbers, and availability-friendly variants.

Generate brandable business, startup, product, and project names from keywords.

Generate social media hashtags from topics, keywords, and captions.

Generate robots.txt rules for crawlers, sitemaps, disallowed paths, and crawl delay.

Generate .gitignore files for popular languages, frameworks, editors, and operating systems.

Create QR codes for URLs, text, email, phone, SMS, and Wi-Fi.

Compress JPG, PNG, and WebP images in your browser.

Resize images by width, height, percentage, or preset sizes.

Convert images between PNG, JPG, and WebP locally in your browser.

Crop images by dragging a crop box or using common aspect ratios.

Generate favicon PNG sizes and an HTML snippet from one image.

Convert images to Base64 data URLs for CSS, HTML, and APIs.

Decode Base64 image strings and data URLs into downloadable images.

Merge multiple PDF files into one combined PDF in your browser.

Extract selected pages or page ranges from a PDF.

Remove unwanted pages from a PDF and download the cleaned file.

Rotate all pages or selected pages in a PDF by 90, 180, or 270 degrees.

View PDF page count, title, author, subject, creator, producer, and dates.

Paste HTML and audit title, meta description, canonical, robots, viewport, and social tags.

Preview and generate Open Graph and Twitter/X card tags for social sharing.

Preview how a page title, URL, and meta description may look in Google search results.

Test whether a URL path is allowed or blocked by pasted robots.txt rules.

Build campaign tracking URLs with utm_source, utm_medium, utm_campaign, and more.

Estimate tokens, words, characters, and prompt size for GPT and Claude-style LLM prompts.

Estimate LLM API costs from input tokens, output tokens, model pricing, and request volume.

Plan how much prompt, memory, tool output, and response budget fits in an LLM context window.

Escape prompts into JSON-safe strings and unescape JSON strings back into readable text.

Build valid OpenAI-style chat messages JSON from system, user, and assistant fields.

Build Anthropic Messages API JSON from system, user, and assistant fields.

Generate a JSON Schema-style function/tool definition from fields and descriptions.

Convert a pasted JSON Schema object into OpenAI or Anthropic tool definitions.

Generate MCP server configuration JSON for stdio, HTTP, and environment-variable based servers.

Compare two prompt versions and highlight added, removed, and changed lines.

Clean, structure, and format rough system prompts into consistent sections for agent instructions.

Remove common AI wrappers, markdown fences, citations, and extra whitespace from pasted LLM output.

Convert a markdown transcript with role headings into chat messages JSON for LLM APIs.

Format messy chat logs into clean Markdown, JSON messages, or readable plain text.

Turn prompt and expected-answer rows into JSONL examples for LLM evaluation datasets.

Calculate percentages, percentage change, and percentage of a number.

Parse cron expressions and see the human-readable schedule.

Calculate age in years, months, days, and total days from a birth date.

Calculate the time between two dates in days, weeks, months, and years.

Estimate monthly payment, total interest, and total cost for a loan.

Project investment growth with contributions, interest rate, and compounding.

Calculate proportional width, height, and common aspect ratios for images and video.