File FormatsJanuary 10, 2025• 4 min read

PNG vs JPG: Which Image Format Should You Use?

Choosing the right image format matters more than most people realise. Using the wrong one can make your website painfully slow, your logo look unprofessional, or your photo quality disappear. Here's everything you need to make the right call every time.

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GenZDoc Team·

The GenZDoc team builds free, privacy-first file tools and writes practical guides on PDF compression, image conversion, and everyday file management.

Real-Life Example: The E-commerce Product Photo Problem

A small clothing store owner switched her WooCommerce site's product images from JPG to PNG because she thought "better quality means better sales." Within a week, her Google PageSpeed score dropped from 78 to 41. Her product images, each a 3–4MB PNG, were taking 8–12 seconds to load on mobile.

After switching back to optimised JPGs at 80% quality, each image was under 200KB, page load time halved, and her bounce rate dropped noticeably. The "lower quality" JPGs were actually indistinguishable from the PNGs on screen for product photos.

The lesson: PNG is not "better" than JPG. It's better for the right task. Understanding which is which can directly affect your business or project.

Quick Comparison

FeaturePNGJPG
Transparency✅ Yes❌ No
File SizeLargerSmaller
Best ForGraphics, LogosPhotos
CompressionLosslessLossy
QualityPerfectVariable

When to Use PNG

PNG (Portable Network Graphics) is ideal for:

  • Logos and icons - Sharp edges stay crisp
  • Graphics with text - Text remains readable
  • Images needing transparency - Alpha channel support
  • Screenshots - Captures exact pixels
  • Digital art - Preserves every detail

When to Use JPG

JPG (JPEG) is best for:

  • Photographs - Millions of colors, natural gradients
  • Web images - Smaller file sizes load faster
  • Social media - Most platforms prefer JPG
  • Email attachments - Keep file sizes manageable
  • Product photos - Good quality at small sizes

Common Mistakes to Avoid

  • Saving photos as PNG for "better quality": Photo PNG files are massive (often 5–10x the size of a comparable JPG) with no visible quality gain on screen. Use JPG for photographs and reserve PNG for graphics, logos, and anything needing transparency.
  • Resaving a JPG multiple times: Every time you open and save a JPG, it re-compresses and loses a tiny bit of quality. After 10–20 resaves, the degradation becomes visible. Always keep the original file and only export a new JPG when you need to share.
  • Using PNG on a website when speed matters: Large PNG files slow down page loading significantly, which directly impacts SEO and user experience. Run all web images through an image compressor before uploading, regardless of format.

Pro Tips for Image Format Choices

💡 Try WebP for the best of both worlds

WebP supports both lossy and lossless compression (like both JPG and PNG) and typically produces 25–35% smaller files than equivalent JPGs at the same visual quality. All modern browsers support it. If your platform accepts WebP, use it for web images.

💡 Keep source files in their original format

Always keep your original high-resolution source file (whether RAW, TIFF, or PSD). Only export to JPG or PNG for sharing/uploading. Converting back and forth between formats degrades quality, so treat your exports as one-way outputs.

The Bottom Line

Rule of thumb: Use JPG for photos and complex images. Use PNG for graphics, logos, and images requiring transparency.

Need to convert between formats? Try our free converter:

Convert PNG ↔ JPG →