Developer Tools — Free Online Utilities
Free online tools for developers and AI users. LLM token counter, API cost calculator, JSON formatter, and more. No registration required.
AI Stack Builder — Find Your Perfect LLM + Vector DB + …
Answer 5 questions about your project, get a tailored AI stack recommendation. LLM choice (GPT-4o / Claude / Gemini / …
Open Tool →Hreflang Tags Generator — Multi-Language & International SEO
Generate copy-paste-ready hreflang link tags for multi-language and international SEO. Map each language to its URL, add …
Open Tool →LLM API Cost Calculator — GPT-4, Claude, Gemini
Calculate LLM API monthly cost. Enter your input/output tokens, requests per day, and pick a model — get instant cost …
Open Tool →LLM Model Recommender 2026 — Pick the Right LLM by Use Case, …
Free decision engine for choosing the right LLM in 2026. Answers 5 questions (use case / budget / context / privacy / …
Open Tool →LLM Token Counter — GPT-4, Claude, Gemini Tokenization …
Free online LLM token counter. Compare how OpenAI GPT-4 / GPT-4o, Anthropic Claude, and Google Gemini tokenize your …
Open Tool →llms.txt Generator — Help AI Crawlers (ChatGPT, Claude, …
Generate a valid llms.txt file for your website in seconds. Help AI crawlers like ChatGPT, Claude, and Perplexity …
Open Tool →MCP Tool Builder — Generate Model Context Protocol Tool …
Free online MCP Tool Definition Generator. Paste a Python or TypeScript function signature and get spec-compliant MCP …
Open Tool →Meta Tags Generator — SEO Title, Description, Open Graph & …
Generate copy-paste-ready HTML head meta tags — SEO title, description, canonical, Open Graph, and Twitter Card — from …
Open Tool →OG Card Preview — Facebook / Twitter / LinkedIn Social Share …
Live preview how your link looks when shared on Facebook, Twitter, LinkedIn, and Slack. Paste a URL or fill in OG meta …
Open Tool →Prompt Optimizer — Restructure, Trim Fillers, Save Tokens …
Free online Prompt Optimizer for AI coding agents and LLM workflows. Detects filler words, restructures into the …
Open Tool →robots.txt Generator — With AI Crawler Controls (GPTBot, …
Generate a clean robots.txt with one click — set sitemap, disallow paths, and block AI crawlers like GPTBot, …
Open Tool →Schema.org JSON-LD Generator — Article / Organization / FAQ …
Generate copy-paste-ready Schema.org JSON-LD structured data for Article, Organization, FAQPage, Product, and …
Open Tool →Top 10 Free MCP Tools in 2026: Best Model Context Protocol …
The 10 best free MCP servers for Claude, Cursor, and any MCP-compatible AI client — filesystem, web search, memory, …
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