Converting HEIC to PNG gives you the highest quality output for your iPhone photos. PNG uses lossless compression, meaning no quality is lost during the conversion process. This is ideal for images you plan to edit further or need to preserve in the highest possible quality.
The resulting PNG files will be significantly larger than the original HEIC files since HEIC uses more efficient compression. A 3MB HEIC photo might become a 12MB PNG. However, the quality preservation is worth it for editing workflows.
With ImgTools, upload your HEIC file, switch to the Convert tab, and select PNG as the output format. The conversion preserves all pixel data from the HEIC source.
Note that HEIC supports 16-bit color depth while PNG-24 (the standard PNG format in web browsers) supports 8-bit per channel. The browser Canvas API used by ImgTools outputs 8-bit PNG, which is sufficient for screen display but represents a reduction from HEIC's higher color depth.
All processing happens locally in your browser. Your iPhone photos are never uploaded to any server.