How to Batch Convert Hundreds of HEIC Files at Once

Transferring years of iPhone photos to a new computer or uploading to a platform that doesn’t accept HEIC? Converting files one at a time isn’t practical. Here’s how to handle bulk conversions efficiently.

Browser-based batch conversion

The fastest method for most people is to use a browser-based converter that supports batch processing. At heic.site, you can drag an entire folder of HEIC files at once. The converter processes them sequentially in your browser and packages the results as a downloadable ZIP file.

This approach has two key advantages:

Privacy — all processing happens locally in your browser. Your photos never leave your device, which matters when converting personal or sensitive images.
No installation — works on any computer with a modern web browser. No software to download, no account to create.

For Safari users on Mac, the conversion is especially fast — Safari can decode HEIC natively at 17-39x the speed of the WebAssembly decoder used by other browsers.

Tips for large batch conversions

Choose the right format. JPG is the universal choice for sharing. WebP offers 25-35% smaller files with the same quality, but has less universal support. PNG is lossless but files are 3-5x larger.

Quality settings matter. A quality of 92 for JPG produces files that are visually identical to the HEIC original. Dropping to 85 saves about 30% more space with minimal visible difference on photos. Below 80, you’ll start to notice artifacts.

Process in batches. While the converter handles multiple files, your browser has limited memory. For collections of hundreds of files, process 50-100 at a time to avoid memory issues on older devices.

Use ZIP downloads. When converting more than a few files, the ZIP download option saves time by packaging everything into a single download rather than clicking download for each file individually.

Organizing converted files

After conversion, you’ll likely want to organize the output. Here are some practical approaches:

Keep the originals. HEIC files have higher quality potential (16-bit color). Store them as your archive and use the JPGs for sharing.
Match folder structure. If your originals are organized by date or event, maintain the same structure for converted files.
Use descriptive filenames. The converter preserves original filenames and just changes the extension, so your naming conventions carry over.

When to consider Pro cloud conversion

For very large collections (thousands of files) or situations where your computer struggles with the processing load, cloud-based conversion can be faster. heic.site Pro offers server-side conversion that handles heavy workloads without taxing your device.