Click, drop, or paste the main photo here
Clear, well-lit faces work best
Pick the one photo the mosaic should look like from far away (e.g., a portrait of the birthday person).
Add ALL the small photos (50+ recommended, hundreds welcome). iPhone HEIC photos work directly — no converting needed. Select many at once, drag them in, or just Ctrl/Cmd+V paste — pasted photos land here by default.