Free tools

Developer & maker utilities

Free interactive tools for AI developers, electronics makers, and embedded engineers.

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Calculator
AI API Cost Calculator
Estimate your monthly costs for OpenAI, Anthropic, and other AI APIs. Compare pricing across GPT-4o, Claude, Llama, and more.
Interactive tool Open tool →
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Utility
Prompt Token Counter & Cost Estimator
Paste any prompt and instantly see the token count, estimated cost per call, and cost projections for different AI models.
Interactive tool Open tool →
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Reference
ESP32-S3 Pinout Quick Reference
Interactive pinout diagram for ESP32-S3 with GPIO functions, ADC channels, I2C/SPI buses, and notes on restricted pins.
Interactive tool Open tool →
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Utility
TTS Voice Preview & Comparison
Compare text-to-speech voices across OpenAI, ElevenLabs, and Kokoro side by side with your own text.
Coming soon
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Calculator
Watch Face Resolution Calculator
Calculate optimal image dimensions, file sizes, and frame rates for custom watch face animations on different displays.
Coming soon
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Calculator
Battery Life Estimator for ESP32 Projects
Enter your battery capacity, Wi-Fi usage pattern, display brightness, and sleep cycles to estimate runtime.
Coming soon
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