How to Batch Convert Multiple Images at Once (JPG, PNG, WEBP)

If you need to convert a folder of JPG product photos to WEBP for a website, or change 50 PNG screenshots to compressed JPGs, doing it one by one is painfully slow. Batch conversion handles all of them in a single operation. Here are the best approaches depending on how many images you have and what tools you're comfortable using.

Why batch convert images?

The most common scenarios for batch conversion:

E-commerce product photography: A photoshoot produces 200 JPG files. Your website requires WEBP. You need all 200 converted without processing each one individually.

Website optimization: A developer inherits a website with hundreds of large PNG images that need converting to compressed JPG or WEBP to improve page load speed.

Client deliverables: A photographer needs to deliver high-resolution TIFFs converted to JPGs at a specific quality setting.

Archiving: Converting a collection of PNGs to a more space-efficient format to reduce storage usage.

Method 1: BG Bueno Image Converter (browser-based, no installation)

BG Bueno's Image Converter supports batch conversion directly in the browser. You can upload multiple files at once and convert them all in a single step.

1. 1Go to the Image Converter tool.
2. 2Upload multiple images using the file picker or drag-and-drop. The tool accepts JPG, PNG, and WEBP files.
3. 3Select your target format (JPG, PNG, or WEBP) and quality setting.
4. 4Click Convert All.
5. 5Download each converted file individually, or use the Download All button to save them all at once.

Best for: Converting between JPG, PNG, and WEBP when you don't want to install software. Handles typical web and photography workflows. All processing is done in your browser — no uploads.

Limitation: Each file is downloaded separately (or in a batch), not packaged as a ZIP. For very large batches (100+ files), a desktop tool may be more convenient.

Method 2: IrfanView (Windows, free)

IrfanView is a lightweight free image viewer and editor that includes powerful batch processing. It handles virtually every image format and is the fastest desktop option for Windows.

1. 1Download and install IrfanView (irfanview.com) — it's free.
2. 2Open IrfanView → File → Batch Conversion/Rename.
3. 3Add your files using the file browser, or use "Add all files in folder."
4. 4Set the output format (JPG, PNG, WEBP, etc.) and quality settings.
5. 5Set the output directory.
6. 6Click Start Batch.

IrfanView can process hundreds of images in seconds. It also supports resizing, watermarking, and renaming as part of the same batch operation.

Best for: Large batches on Windows. Fast, reliable, format support is extensive.

Method 3: Preview (Mac, built-in)

Mac users have batch conversion built into Preview without installing anything.

1. 1Select all the images you want to convert in Finder.
2. 2Right-click → Open With → Preview.
3. 3All images open in Preview's sidebar.
4. 4Select all images in the sidebar (Cmd+A).
5. 5File → Export Selected Images.
6. 6Choose format (JPG, PNG, HEIC, TIFF) and quality.
7. 7Choose an output folder.

Preview exports all selected images in one operation. Fast and convenient for moderate batches.

Limitation: Preview doesn't support WEBP export, only import. For WEBP output on Mac, use a browser tool or install a third-party converter.

Method 4: Command line with ImageMagick (advanced, all platforms)

For developers and power users, ImageMagick is the most flexible batch processing option. It's free, runs on Windows, Mac, and Linux, and can handle arbitrarily complex batch operations.

To convert all JPGs in a folder to WEBP:

mogrify -format webp -quality 82 *.jpg

To resize and convert:

mogrify -format webp -quality 82 -resize 1200x *.jpg

ImageMagick supports hundreds of formats and can script virtually any combination of operations. Requires comfort with the command line.

Method 5: Adobe Lightroom (paid)

If you already use Lightroom for photo management, its Export function handles batch conversion efficiently. Select photos, File → Export, set your format and quality, and export all selected photos at once.

Lightroom's batch export is excellent for photography workflows where you're also doing color correction and editing as part of the same process.

Choosing the right method

Tips for batch conversion quality

Set quality to 82 for JPG and WEBP in most cases. This gives excellent visual quality at 60–70% smaller file size than quality 100.

Don't reconvert from an already-compressed source. Converting JPG → WEBP → JPG introduces cumulative compression artifacts. Always work from the original uncompressed or highest-quality version.

Keep originals. Never overwrite your originals with converted versions. Always output to a new folder.

Check a sample first. Before running a batch of 500 images, convert 5–10 and review the quality. Adjust settings if needed, then run the full batch.