Hanabi 3D is a physics-based Japanese fireworks (hanabi) simulator that runs entirely in the browser using Three.js particles. Every star is integrated in real SI units — gravity plus quadratic air drag — so shells rise, decelerate and droop the way real ones do, instead of following a scripted animation.

Twelve shell types seen at Japanese fireworks festivals are reproduced: chrysanthemum (菊), peony (牡丹), kamuro / willow (冠菊), nishiki kamuro (錦冠), cored shells (芯入り), colour-changing (色変わり), strobe (点滅), crossette (十字), ring and heart pattern shells (型物), palm (椰樹) and senrin (千輪). Their shape, colour transitions and glitter behaviour were tuned against 29 long-exposure photographs taken at fireworks festivals in Japan between 2023 and 2025.

Gravity, air drag, time scale, trail length, lens focal length, glow and exposure are adjustable in real time, and clicking anywhere in the sky launches a shell toward that position. Interface available in English and Japanese.

Last updated: 2026-09-01