I Built 6 Free Developer Tools for AI APIs, Cron, Docker, and Self-Hosting

I keep running into the same friction points: "How much will this prompt cost on GPT-4o vs Claude?", "What's the cron syntax for every Monday at 9am?", "Is there an open-source alternative to Notion I can self-host?"

I got tired of Googling each time, so I built a set of free tools that solve these problems. No login, no API keys, no tracking — everything runs in your browser.

Here's what each one does.

1. AI Prompt Cost Calculator

Paste any prompt and instantly see the cost across 10 AI models: GPT-4o, GPT-4o Mini, o3, o4-mini, Claude Sonnet 4, Claude Haiku 4, Gemini 2.5 Pro, Gemini 2.5 Flash, Llama 4 Maverick (via Groq), and DeepSeek R1.

I Built 6 Free Developer Tools for AI APIs, Cron, Docker, and Self-Hosting

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