JPG vs PNG: Which Image Format Should You Use?

Choosing between JPG and PNG is one of the most common decisions in digital image work. Both formats are widely supported, but they are designed for very different purposes. Picking the wrong one can mean unnecessarily large files, visible quality loss, or broken transparency. This guide explains when to use each format and why.

What Is JPG?

JPG (also written JPEG) is a lossy compression format designed for photographs and complex, colour-rich images. When you save a file as JPG, the encoder discards some image data to reduce file size. The amount of data discarded is controlled by a quality setting — at 85 % quality, most photographs look nearly identical to the original while the file is 60–80 % smaller.

JPG is best for:

• Photographs and camera images
• Social media profile pictures and cover photos
• Blog post hero images
• Product photography for e-commerce websites
• Any image with many smooth colour gradients

JPG does not support transparency. If you save a logo with a transparent background as JPG, the transparent areas become white (or another solid colour depending on the application). If you need transparency, use PNG instead.

What Is PNG?

PNG (Portable Network Graphics) is a lossless compression format. Lossless means the encoder never throws away image data — every pixel is stored exactly as it was in the original. PNG was specifically designed to replace older formats for web graphics.

PNG is best for:

• Logos, icons, and illustrations that need a transparent background
• Screenshots, diagrams, and interface mockups
• Images with sharp edges and flat areas of colour
• Any image where pixel-perfect accuracy matters
• Graphics intended for further editing

PNG files are larger than JPG for photographic content. A photo saved as PNG can be 3–10× larger than the same image saved as JPG at 85 % quality. For photographs published on a website, JPG is almost always the better choice.

Key Differences at a Glance

| Feature | JPG | PNG |

|---|---|---|

| Compression type | Lossy | Lossless |

| Transparency support | No | Yes (full alpha channel) |

| Best for | Photographs | Graphics, logos, screenshots |

| Typical file size | Small | Larger |

| Quality degradation | Yes (at low quality settings) | Never |

| Animation support | No | No (use GIF or WebP for animation) |

| Browser support | Universal | Universal |

When File Size Matters Most

If you are optimising images for a website, file size directly affects how quickly your pages load. Larger images increase page weight and can hurt your Core Web Vitals scores. As a rule:

1. Use JPG at 80–85 % quality for photographs. This gives an excellent balance of visual quality and file size.
2. Use PNG for logos, icons, and any graphic that requires transparency or sharp edges.
3. Consider WebP if you need the benefits of both — WebP supports transparency, delivers smaller files than both JPG and PNG, and is supported by all modern browsers.

A Practical Decision Guide

Ask yourself three questions:

1. Does the image contain transparency?

If yes, you must use PNG (or WebP). JPG cannot store transparent pixels.

2. Is it a photograph or a graphic?

Photographs compress well with JPG and look nearly identical at 80 % quality. Graphics, logos, and diagrams usually look better as PNG because their sharp edges and flat colours do not tolerate lossy compression.

3. How important is the smallest possible file size?

If minimising file size is the priority and your audience uses modern browsers, convert to WebP. WebP typically produces files 25–35 % smaller than equivalent JPG at the same visual quality.

Converting Between JPG and PNG

You can convert between JPG and PNG directly in your browser using Free Image Converter. The conversion is entirely private — your image is processed locally on your device and never uploaded to any server.

• Convert JPG to PNG — useful when you need to add transparency to an existing photo, or when a platform requires PNG specifically.
• Convert PNG to JPG — useful when you need to reduce file size for a photo that was originally saved as PNG.

Keep in mind that converting a JPG to PNG does not recover quality that was lost when the image was originally compressed as JPG. The output PNG will be lossless, but it will preserve the existing compression artefacts rather than eliminating them.

Summary

Use JPG for photographs where file size matters. Use PNG when you need transparency or when working with graphics that have sharp edges. When in doubt, try WebP — it handles both use cases well while delivering smaller files. And whatever format you choose, you can always convert between them quickly and privately right here.