Guides, tutorials, and documentation for our free developer APIs.
API GuideGenerate QR codes via REST API. Support for PNG, SVG, base64 output. Custom colors, sizes, and styles. Free tier available.
API GuideConvert text to natural speech with our TTS API. 300+ voices, 70+ languages, multiple audio formats. Free tier with generous limits.
API GuideValidate email addresses with DNS/MX lookup, disposable detection, and typo suggestions. Batch validation support. Free tier.
API GuideComplete PDF toolkit API: merge, split, compress, rotate, watermark, extract text, add page numbers. Free tier available.
API GuideGet real-time cryptocurrency prices, market data, historical charts, and trending coins. Coverage for 10,000+ coins. Free tier.
API GuideReal-time currency conversion and exchange rates from ECB. Support for 31+ currencies with historical data. Free tier.
API GuideLookup IP addresses for geolocation data: country, city, timezone, ISP, and more. Batch lookup support. Free tier.
API GuideCapture full-page screenshots of any website. Custom viewport, format options. Headless Chrome powered. Free tier.
API GuideGenerate placeholder images, social media cards, OG images, avatars, badges, gradients, and patterns via API. Free tier.
API GuideAI-powered text tools: summarization, translation, rewriting, sentiment analysis, keyword extraction. Local AI, no data sharing. Free tier.
API GuideGenerate professional PDF invoices with customizable templates. Line items, tax, discounts, logos. Free tier available.
GuideCurated list of the best free APIs for developers: QR codes, PDFs, AI text, crypto, currency, email validation, screenshots, and more.
GuideInstall our MCP server to get 30+ developer tools directly in Claude Code, Cursor, Windsurf, and other AI coding assistants.
TutorialStep-by-step guide to building production REST APIs with FastAPI. Covers routing, validation, authentication, database integration, deployment with systemd, and rate limiting.
TutorialComplete guide to API authentication: API keys, OAuth 2.0, JWT tokens, rate limiting, and security best practices for REST APIs in 2026.
ComparisonCompare the best QR code generator APIs in 2026: pricing, features, styles, output formats. Find the right QR API for your project.
GuideCollection of free browser-based developer tools: JSON formatter, Base64 encoder, hash generator, UUID generator, regex tester, JWT decoder, password generator. No installation needed.
TutorialLearn how to programmatically merge, split, and compress PDFs using a REST API. Python, JavaScript, and cURL code examples included.
ComparisonCompare the best text-to-speech APIs in 2026. Features, pricing, voice quality, language support. Google, Amazon, Azure, and free alternatives.
TutorialAutomate invoice creation in your app with a PDF invoice API. Generate professional invoices with line items, tax, logos. Python & JavaScript examples.
ComparisonCompare the best free weather APIs: Open-Meteo, OpenWeatherMap, WeatherAPI, Tomorrow.io, Visual Crossing. Code examples, pricing, and feature comparison.
ComparisonCompare the best free LLM APIs: Google AI Studio (Gemini), Groq, OpenRouter, HuggingFace, Cloudflare Workers AI, Ollama. Code examples and pricing.
ComparisonCompare the best free web scraping APIs: ScraperAPI, Apify, Bright Data, Crawlbase. Plus Screenshot API for visual capture. Code examples included.
ComparisonCompare the best free OCR APIs and tools: OCR.space, Google Cloud Vision, Tesseract, Eden AI, EasyOCR. Python code examples and accuracy comparison.
API GuideShorten URLs, track clicks, extract Open Graph metadata, detect redirects. Free URL toolkit API with Python, JavaScript, and cURL examples.
GuideComplete guide to free APIs every startup needs: PDF processing, email validation, QR codes, invoicing, AI text tools, and more. One API key for 13 services.
API GuideGenerate MD5, SHA-256, SHA-512, BLAKE2b hashes via REST API. Plus UUID generation, Base64 encoding, password generation, JWT decoding. Free developer tools API.
ComparisonCompare the best free translation APIs for developers: Google Translate alternatives, LibreTranslate, MyMemory, Lingva. Code examples and pricing.
ComparisonCompare the best free SMS APIs and Twilio alternatives: Vonage, Plivo, MessageBird, TextBelt. Code examples for sending SMS via REST API.
ComparisonCompare the best free stock market APIs: Alpha Vantage, Finnhub, Twelve Data, Polygon.io, Yahoo Finance. Real-time quotes, historical data, and technical indicators.
ComparisonCompare the best free file conversion APIs: CloudConvert, Zamzar, ConvertAPI, PDF.co. Convert PDFs, images, documents, and videos via REST API.