llms.txt
# makr.io
> 85+ free browser tools and 100+ copiable Claude Code skills for solo founders and product teams. JSON formatter, PDF merger, color picker, plus skills for engineering, backend, mobile, DevOps, product, design, marketing, and AI.
Every tool runs in the browser: files and text are processed on the device, not uploaded.
## Design & Graphics Tools
Create beautiful mobile mockups, convert graphics, and explore colors. All tools run in your browser.
- [Design & Graphics Tools overview](https://www.makr.io/design)
- [SVG to PNG](https://www.makr.io/design/svg2png): Convert SVG files to PNG images
## Color Tools Suite
Online color tools for designers and developers. Color picker, palette generator, gradient creator, contrast checker, color blindness simulator, and more.
- [Color Tools Suite overview](https://www.makr.io/design/color)
- [Color Picker](https://www.makr.io/design/color/color-picker): Online color picker and converter. Pick colors and convert between HEX, RGB, HSL, and HSV formats instantly. No sign-up required.
- [Palette Generator](https://www.makr.io/design/color/palette-generator): Color palette generator. Create harmonious color schemes using color theory principles — complementary, analogous, triadic, tetradic, and monochromatic.
- [Gradient Generator](https://www.makr.io/design/color/gradient-generator): CSS gradient generator. Create beautiful linear and radial gradients with multiple color stops and directions. Copy CSS code instantly.
- [Contrast Checker](https://www.makr.io/design/color/contrast-checker): WCAG contrast ratio checker. Verify color accessibility compliance for AA and AAA standards with real-time text preview.
- [Color Blindness Simulator](https://www.makr.io/design/color/color-blindness): Color blindness simulator. Test how your colors appear with protanopia, deuteranopia, tritanopia, and other types of color vision deficiency.
- [Shade Generator](https://www.makr.io/design/color/shade-generator): Shade and tint generator. Generate lighter tints and darker shades of any color. Create Tailwind-style color scales (50-950).
- [Image Color Extractor](https://www.makr.io/design/color/image-extractor): Image color extractor. Upload any image and extract its dominant colors to create palettes. All processing happens in your browser.
- [Brand Colors Library - Official Brand Color Codes](https://www.makr.io/design/color/brand-colors): Find official hex color codes for 55+ popular brands like Google, OpenAI, Anthropic, Cursor, Spotify, Netflix, Stripe, Apple, and more. Copy HEX values instantly for your design projects.
## Mobile Design Tools
Mobile app design tools. Generate app icons, store screenshots, feature graphics, and splash screens.
- [Mobile Design Tools overview](https://www.makr.io/design/mobile)
- [App Icon Generator](https://www.makr.io/design/mobile/app-icon): Create beautiful app icons with text, emoji, or images for iOS and Android. Generate all required sizes instantly.
- [Store Screenshots](https://www.makr.io/design/mobile/store-screenshots): Generate professional app store screenshot mockups for iPhone, iPad, and Android devices.
- [Feature Graphic](https://www.makr.io/design/mobile/feature-graphic): Create Google Play Store feature graphics at the required 1024x500 size with gradients, text, and images.
- [Adaptive Icon](https://www.makr.io/design/mobile/adaptive-icon): Generate Android adaptive icons with separate foreground and background layers. Preview different mask shapes.
- [Splash Screen](https://www.makr.io/design/mobile/splash-screen): Create splash screen images for mobile apps with customizable backgrounds, logos, and text.
## Code Tools Suite - Developer Tools
Developer tools. Format code, convert data, generate UUIDs/hashes/JWTs, test regex, and more. Terminal-themed.
- [Code Tools Suite - Developer Tools overview](https://www.makr.io/code)
- [JSON Formatter](https://www.makr.io/code/format-json): Format, validate, minify, and beautify JSON online
- [Code Formatter](https://www.makr.io/code/format-code): Format and beautify code with proper indentation
- [SQL Formatter](https://www.makr.io/code/format-sql): Format and beautify SQL queries
- [Base64 Encoder](https://www.makr.io/code/base64): Encode and decode Base64 strings
- [JSON ↔ YAML Converter](https://www.makr.io/code/json-yaml): Convert between JSON and YAML formats
- [JSON → TypeScript](https://www.makr.io/code/json-typescript): Generate TypeScript interfaces from JSON
- [UUID Generator](https://www.makr.io/code/uuid): Generate random UUIDs (v4)
- [Hash Generator](https://www.makr.io/code/hash): Generate MD5, SHA-1, SHA-256, SHA-512 hashes
- [JWT Decoder](https://www.makr.io/code/jwt): Decode and inspect JSON Web Tokens
- [Cron Generator](https://www.makr.io/code/cron): Build and understand cron expressions
- [Regex Tester](https://www.makr.io/code/regex): Test and debug regular expressions
- [Timestamp Converter](https://www.makr.io/code/timestamp): Convert between Unix timestamps and dates
- [String Utilities](https://www.makr.io/code/string): Transform, encode, and manipulate strings
- [Color Picker](https://www.makr.io/code/color-picker): Pick colors and convert between formats
- [Diff Checker](https://www.makr.io/code/diff): Compare text and find differences
- [TOON ↔ JSON Converter](https://www.makr.io/code/toon-json): Convert between TOON and JSON formats
- [Code to Image Studio](https://www.makr.io/code/code-to-image): Turn code snippets into beautiful, shareable images
## Email Tools
Preview HTML emails, check DMARC records, and analyze headers. All tools run in your browser.
- [Email Tools overview](https://www.makr.io/email)
- [Email Preview](https://www.makr.io/email/preview): Preview HTML emails across devices
- [Email Headers Analyzer](https://www.makr.io/email/headers): Analyze email headers for delivery issues
- [DMARC Domain Checker](https://www.makr.io/email/dmarc): Check DMARC records for email authentication
## HTML Tools Suite
Format, validate, convert, and optimize HTML with professional-grade tools. All processing in your browser.
- [HTML Tools Suite overview](https://www.makr.io/html)
- [HTML to PDF](https://www.makr.io/html/html-to-pdf): Convert HTML to PDF documents
- [HTML Validator](https://www.makr.io/html/html-validator): Validate HTML syntax and structure
- [HTML Viewer](https://www.makr.io/html/html-viewer): Preview HTML code in real-time
- [HTML Minifier](https://www.makr.io/html/html-minifier): Minify HTML by removing whitespace
- [HTML Formatter](https://www.makr.io/html/html-formatter): Format and beautify HTML code
- [HTML to Markdown](https://www.makr.io/html/html-to-markdown): Convert HTML to Markdown format
- [Markdown to HTML](https://www.makr.io/html/markdown-to-html): Convert Markdown to HTML format
- [HTML Diff](https://www.makr.io/html/html-diff): Compare two HTML documents
- [Email Template Tester](https://www.makr.io/html/email-template-tester): Test and preview HTML email templates
- [OG Image Generator](https://www.makr.io/html/og-image-generator): Generate Open Graph images for social sharing
- [Favicon Generator](https://www.makr.io/html/favicon-generator): Generate favicons from images
- [CSS Minifier](https://www.makr.io/html/css-minifier): Minify CSS stylesheets
- [Base64 Encoder](https://www.makr.io/html/base64-encoder): Encode files and text to Base64
- [HTML Entity Encoder](https://www.makr.io/html/html-entity-encoder): Encode and decode HTML entities
## JSON Tools Suite
Format, validate, convert, and transform JSON with professional-grade tools. All processing happens in your browser.
- [JSON Tools Suite overview](https://www.makr.io/json)
- [JSON Formatter](https://www.makr.io/json/formatter): Format and beautify JSON with customizable indentation
- [JSON Validator](https://www.makr.io/json/validator): Validate JSON syntax and structure
- [JSON Minifier](https://www.makr.io/json/minifier): Minify JSON by removing whitespace
- [JSON Diff](https://www.makr.io/json/diff): Compare two JSON objects and visualize differences
- [TOON Converter](https://www.makr.io/json/toon-converter): Convert between TOON and JSON formats
- [JSON to CSV](https://www.makr.io/json/to-csv): Convert JSON arrays to CSV format
- [JSON to YAML](https://www.makr.io/json/to-yaml): Convert JSON to YAML format
- [JSON to XML](https://www.makr.io/json/to-xml): Convert JSON to XML format
- [JSON to TypeScript](https://www.makr.io/json/to-typescript): Generate TypeScript types from JSON
- [Schema Generator](https://www.makr.io/json/schema-generator): Generate JSON Schema from JSON data
- [Schema Validator](https://www.makr.io/json/schema-validator): Validate JSON against a JSON Schema
- [Path Finder](https://www.makr.io/json/path-finder): Find and copy JSON paths
- [JSON Query](https://www.makr.io/json/query): Query JSON with JSONPath expressions
- [JSON Merge](https://www.makr.io/json/merge): Deep merge multiple JSON objects
- [JSON Repair](https://www.makr.io/json/repair): Fix broken or malformed JSON
- [JSON Escape](https://www.makr.io/json/escape): Escape and unescape JSON strings
- [Mock Generator](https://www.makr.io/json/mock-generator): Generate mock JSON data from schemas
- [JSON Visualize](https://www.makr.io/json/visualize): Visualize JSON as an interactive tree
- [JSON Playground](https://www.makr.io/json/playground): Interactive JSON editor and explorer
## PDF Tools Suite
Everything you need for PDFs. Merge, split, compress, convert, and edit — all processed in your browser.
- [PDF Tools Suite overview](https://www.makr.io/pdf)
- [Merge PDFs](https://www.makr.io/pdf/merge): Combine multiple PDF files into one
- [Split PDF](https://www.makr.io/pdf/split): Split a PDF into separate files
- [Compress PDF](https://www.makr.io/pdf/compress): Reduce PDF file size
- [PDF to Images](https://www.makr.io/pdf/pdf-to-images): Convert PDF pages to images
- [Images to PDF](https://www.makr.io/pdf/images-to-pdf): Convert images to a PDF file
- [Rotate Pages](https://www.makr.io/pdf/rotate): PDF page rotator. Rotate individual or all pages 90\u00b0, 180\u00b0, or 270\u00b0. Visual thumbnail preview. Your PDF files stay on your device and are not uploaded to our servers.
- [Delete Pages](https://www.makr.io/pdf/delete): Remove pages from a PDF
- [Organize Pages](https://www.makr.io/pdf/organize): Reorder and organize PDF pages
- [Page Numbers](https://www.makr.io/pdf/page-numbers): Add page numbers to a PDF
- [Text Watermark](https://www.makr.io/pdf/watermark): Add text watermarks to PDFs
- [Image Watermark](https://www.makr.io/pdf/image-watermark): Add image watermarks to PDFs
- [Headers & Footers](https://www.makr.io/pdf/headers-footers): Add headers and footers to PDFs
- [Extract Text](https://www.makr.io/pdf/extract-text): Extract text content from PDFs
- [PDF Info](https://www.makr.io/pdf/pdf-info): View PDF metadata and properties
- [Edit Metadata](https://www.makr.io/pdf/edit-metadata): Edit PDF metadata and properties
- [Remove Redactions](https://www.makr.io/pdf/remove-redactions): Remove redaction marks from PDFs
## Security Tools
Analyze HTTP security headers and get actionable recommendations. Runs in your browser.
- [Security Tools overview](https://www.makr.io/security)
- [Security Headers Analyzer](https://www.makr.io/security/headers): Analyze HTTP security headers
## More tools
- [Pomodoro Timer](https://www.makr.io/pomodoro): A simple and effective Pomodoro timer app to boost your productivity
## Claude Code skills
Copy-ready SKILL.md files for agents that read skill folders.
- [Skills overview](https://www.makr.io/skills)
- [Accessibility Audit](https://www.makr.io/skills/accessibility-audit): Audits components and pages against WCAG 2.1 AA criteria, identifies violations by severity, and applies fixes for labels, contrast, keyboard access, ARIA, and semantic structure. Use when reviewing or fixing accessibility issues in a frontend codebase.
- [Build AI Agent Workflows](https://www.makr.io/skills/ai-agent-workflows): Builds AI agent systems with multi-step reasoning loops, tool definitions, planning strategies, memory management, error recovery, and safety guardrails for autonomous task execution. Use when implementing an AI agent that reasons, plans, and uses tools to complete tasks.
- [Build an AI Content Pipeline](https://www.makr.io/skills/ai-content-pipeline): Build an AI content generation pipeline with structured prompts, review workflows, batch generation, quality scoring, and scheduled publishing with human-in-the-loop.
- [Optimize AI Costs](https://www.makr.io/skills/ai-cost-optimization): Reduces AI feature costs through model routing, prompt caching, token budgets, response caching, batch processing, and spend monitoring without sacrificing output quality. Use when optimizing LLM API spend or implementing cost controls for AI features.
- [Evaluate AI Features](https://www.makr.io/skills/ai-evaluation): Builds evaluation infrastructure for AI features — test datasets, automated scoring, LLM-as-judge rubrics, regression detection, and A/B testing across prompt and model variants. Use when measuring, comparing, or monitoring AI output quality.
- [Add an AI Feature](https://www.makr.io/skills/ai-feature): Integrates AI-powered capabilities into an application — classification, generation, summarization, search, or conversation — with provider abstraction, streaming, structured output, and cost controls. Use when adding LLM-driven functionality to a product.
- [Add AI Safety Guardrails](https://www.makr.io/skills/ai-safety-guardrails): Add safety guardrails to AI features — input validation, PII detection, content filtering, prompt injection defense, rate limiting, cost controls, and audit logging.
- [Analytics Setup](https://www.makr.io/skills/analytics-setup): Implements event tracking with a provider-agnostic abstraction layer, covering event taxonomy, user identification, consent handling, and conversion setup. Use when adding metrics and tracking to a web or mobile application.
- [Animation and Micro-Interactions](https://www.makr.io/skills/animation-micro-interactions): Adds purposeful animations and micro-interactions — hover feedback, page transitions, loading shimmer, and state changes — using only GPU-accelerated properties and respecting prefers-reduced-motion. Use when adding motion design to a frontend application.
- [API Design Review](https://www.makr.io/skills/api-design-review): Audits REST or GraphQL API endpoints for naming consistency, proper HTTP methods, error handling, pagination, versioning, and security headers.
- [API Design](https://www.makr.io/skills/api-design): Designs RESTful APIs with routes, validation, error handling, pagination, versioning, and OpenAPI documentation from a feature description. Use when building or extending API endpoints.
- [App Store Optimization](https://www.makr.io/skills/app-store-optimization): Analyzes your iOS or macOS app's store listing and generates optimized title, subtitle, keywords, and description to maximize search visibility and conversion.
- [App Store Submission Preparation](https://www.makr.io/skills/app-store-submission): Prepares a mobile app for Apple App Store and Google Play Store submission including metadata, screenshots, privacy declarations, build configuration, and review guideline compliance. Use when readying an app for store review or publication.
- [Auth Implementation](https://www.makr.io/skills/auth-implementation): Implements authentication and authorization with session or JWT management, OAuth, magic links, protected routes, and security best practices. Use when implementing login, sign-up, or access control.
- [Blog Post](https://www.makr.io/skills/blog-post): Writes complete blog posts with SEO optimization, structured sections, code examples where relevant, and audience-appropriate tone for technical tutorials, product updates, case studies, and thought leadership. Use when writing a blog post for an engineering blog, product blog, or company publication.
- [Design a Caching Strategy](https://www.makr.io/skills/caching-strategy): Implement caching at the right layers — HTTP headers, CDN, Redis, and client-side query cache — to improve performance and reduce costs.
- [Changelog Generator](https://www.makr.io/skills/changelog-generator): Parses git log, groups commits by type (features, fixes, chores), and generates a structured CHANGELOG.md entry with proper semantic versioning.
- [Changelog Page](https://www.makr.io/skills/changelog-page): Builds a public changelog page with categorized entries, optional auto-generation from git history, RSS feed support, and user-centric release communication. Use when creating or restructuring a changelog to keep users informed of product changes.
- [Build an AI Chatbot](https://www.makr.io/skills/chatbot-implementation): Builds a conversational AI chatbot with streaming responses, message history persistence, context window management, tool use, and production-grade error handling. Use when implementing a chat interface powered by an LLM.
- [CI/CD Pipeline with GitHub Actions](https://www.makr.io/skills/ci-cd-pipeline): Generates GitHub Actions CI/CD workflows with lint, typecheck, test, build, and deploy stages, including caching, matrix strategies, and branch protection. Use when setting up or improving continuous integration and deployment pipelines.
- [Code Review](https://www.makr.io/skills/code-review): Performs structured code review with severity-classified findings across correctness, security, performance, and maintainability. Use when the user asks to review code, a file, a diff, or a pull request.
- [Color System](https://www.makr.io/skills/color-system): Generates a complete color system with primary, semantic, and neutral scales, dark mode mappings, and WCAG AA contrast verification, output as CSS custom properties or Tailwind config. Use when creating or overhauling a project's color palette.
- [Competitive Analysis](https://www.makr.io/skills/competitive-analysis): Analyzes competitors across features, pricing, positioning, tech stack, and user experience to identify differentiation opportunities and competitive moats. Produces a structured comparison matrix with strategic recommendations. Use when evaluating a competitor or positioning against the market.
- [Customer Journey Map](https://www.makr.io/skills/customer-journey-map): Maps the full customer lifecycle from awareness through advocacy with stage-specific touchpoints, emotional states, pain points, metrics, and gap analysis, optionally segmented by persona. Use when visualizing the user experience end-to-end, identifying drop-off points, or aligning teams on the customer experience.
- [Dark Mode Implementation](https://www.makr.io/skills/dark-mode-implementation): Implements dark mode with CSS custom properties or Tailwind, including theme context, OS preference detection, localStorage persistence, color token remapping, and per-element verification. Use when adding theme switching support to a frontend.
- [Data Visualization](https://www.makr.io/skills/data-visualization): Builds charts and dashboard layouts by selecting the right chart type per data relationship, configuring a charting library, and handling responsive rendering, accessibility, and performance for large datasets. Use when creating charts, graphs, or data dashboards.
- [Database Backup and Recovery](https://www.makr.io/skills/database-backup): Automate database backups with scheduled dumps, offsite storage, point-in-time recovery, retention policies, and restore testing.
- [Database Schema Design](https://www.makr.io/skills/database-schema): Designs and implements database schemas with migrations, indexes, relationships, and seed data using the project's ORM or raw SQL. Use when setting up or evolving a database structure.
- [Debug From Error](https://www.makr.io/skills/debug-from-error): Classifies errors, reads stack traces bottom-up, distinguishes ro
