How the heic to jpg converter works
A dedicated browser worker decodes the primary HEIC or HEIF still image with libheif, calculates safe output dimensions, redraws the pixels on a canvas, and encodes a new JPG, PNG, or WebP file. The generated file does not copy the source metadata.
output dimensions = source dimensions × selected scaleOriginal mode keeps the decoded dimensions; percentage, maximum-width, and long-edge modes preserve the aspect ratio.
Convert a 4032 × 3024 iPhone photo to JPG
Original-size mode keeps the 4032 × 3024 pixel dimensions and JPG quality controls the lossy encoder. Choosing a 1920-pixel long edge instead produces a 1920 × 1440 image while preserving the 4:3 aspect ratio.
Using the processed image
Keep the exported dimensions, format, transparency, and compression level appropriate for where the image will be used.
<img src="photo-converted.jpg" width="1920" height="1440" alt="Describe the visible photo"><picture>
<source srcset="photo-converted.webp" type="image/webp">
<img src="photo-converted.jpg" width="1920" height="1440" alt="Describe the visible photo">
</picture>Using the result accurately
Use JPG for broadly compatible photographs, PNG when lossless output is more important than file size, and WebP for modern web delivery. Inspect gradients, fine detail, and color after conversion, especially when the source uses HDR or a wide color gamut.
The converter exports the primary still image only. It does not preserve Live Photo video, secondary images, EXIF, location data, depth maps, HDR gain maps, or every color-profile behavior. A converted file can also be larger than its HEIC source.
References: libheif: HEIF and AVIF codec library.