Your numbers stay yours.

Everything you enter is saved locally on your device (in your browser's storage). It never leaves your device unless you choose one of the actions below. Clear your browser data and it's gone.

Signing up (optional) stores your email address and any plans you explicitly save, so you can reload them later. That's handled by Supabase, our authentication and database provider. You can change your password or delete your saved data at any time from Account.

Two optional features use Google's Gemini, and only when you trigger them. Pressing Get tipssends a summary of your plan's figures (ages, balances, contributions, the projected outcome) to generate suggestions. Using Import with AI in a portfolio sends the fund text you paste (or the CSV you upload) so it can be matched to asset classes. No name, email, or account identifier is included, and nothing is sent unless you use these features.

A share link encodes your plan's figures directly in the URL. Anyone you send it to can see those figures (read-only) — so only share it with people you're happy to show. Nothing is stored on a server to create one.

There are no advertising trackers or third-party marketing cookies. If privacy-friendly, cookieless usage analytics are ever added, they won't identify you.

Fireworks is an educational tool with simplified assumptions — see the methodology. It doesn't provide regulated financial advice.