Why convert HEIC to PNG?
Unlike JPEG, PNG uses lossless DEFLATE (LZ77 + Huffman) compression and supports full 8-bit alpha transparency. If you plan to crop, color-grade, or overlay typography onto an iPhone photo, converting HEIC to PNG first prevents DCT ringing and mosquito noise around sharp edges.
Private by design: zero uploads
Your iPhone photos never leave your device. The WebAssembly decoder runs inside your browser's memory sandbox, making it safe for sensitive ID scans, medical photos, and private family albums.
Frequently asked questions
Why is the output PNG file larger than my original HEIC file?
HEIC is a heavily compressed lossy format, whereas PNG is completely lossless. To preserve every pixel without introducing new compression artifacts, PNG stores exact pixel values using lossless DEFLATE compression, which naturally results in a larger file size.
Are my HEIC photos uploaded to a server during conversion?
Never. trsf.it loads a WebAssembly image engine into your browser tab and performs the entire decode and PNG encode on your own CPU.