Free tools

Tools & calculators

A growing set of free, fast tools that run entirely in your browser — nothing you enter is sent to a server.

AI

Compare and estimate LLM API costs across Claude, GPT, and Gemini by tokens and volume.

Calculate monthly EMI, total interest, and view the amortization schedule.

Estimate the future value of your monthly SIP investments.

Add or remove GST with CGST/SGST split for Indian tax rates.

Pretty-print, minify, and validate JSON with error reporting.

Decode a JWT to inspect its header and payload. Runs locally.

Find an exact age in years, months, and days plus next birthday.

Work out percentages, ratios, and increase/decrease with the formula shown.