JPG vs PNG: Which Format Should You Use?

JPG and PNG are the two most common image formats on the web, yet they serve different purposes. Choosing the wrong one leads to blurry text, bloated file sizes, or lost transparency. This guide breaks down the technical differences and gives you a simple decision framework for everyday tasks.

How JPG Works

JPG (JPEG) uses lossy compression — it permanently discards image data to reduce file size. This works well for photographs with smooth color gradients, where the human eye cannot detect minor detail loss. A 4000 × 3000 photo might shrink from 12 MB (RAW) to 2–4 MB as JPG at high quality.

The trade-off appears around sharp edges and text. JPG compression creates visible artifacts — fuzzy halos and blocky patches — around high-contrast boundaries. This makes JPG a poor choice for screenshots, logos, and diagrams even though it excels at photos.

How PNG Works

PNG uses lossless compression — every pixel is preserved exactly. File sizes are larger than JPG for photographic content, but PNG maintains crisp edges on text, line art, and flat-color graphics. PNG also supports an alpha channel for transparency, which JPG does not.

A screenshot saved as PNG at the same dimensions as JPG might be 3–5× larger, but the text remains pixel-perfect and any transparent areas stay transparent.

Quick Decision Guide

• Choose JPG for photographs, social media images, email attachments where size matters, and any image without transparency requirements.
• Choose PNG for screenshots, logos, icons, diagrams, text-heavy graphics, and any image that needs a transparent background.

File Size Comparison

For a typical 1920 × 1080 screenshot with text and UI elements, JPG at 85% quality might be 150 KB while PNG is 800 KB. For a 4000 × 3000 landscape photo, JPG at 90% quality might be 3 MB while PNG is 15 MB. The ratio depends on content complexity — photos compress better in JPG; flat graphics compress better in PNG relative to their visual quality.

Transparency

Only PNG (and WebP with alpha) supports transparency. If you need a logo that overlays on different backgrounds, PNG is the standard choice. Converting a JPG to PNG does not add transparency — the opaque background remains. For true transparency, start from a source that has an alpha channel or use a background removal tool.

Web Performance

Modern websites increasingly use WebP, which offers both lossy and lossless modes plus transparency in a smaller package than PNG or JPG. However, JPG and PNG remain the most universally compatible formats. When converting for web use, JPG for photos and PNG (or WebP) for graphics is still the safe default.

Converting Between Formats

SeerKits Image Converter handles JPG to PNG and PNG to JPG conversion locally in your browser. Remember: converting PNG to JPG reduces file size but may add compression artifacts. Converting JPG to PNG increases file size without recovering lost detail. Always keep your highest-quality original as the master copy.

PDF Export Context

When exporting PDF pages to images, the same rules apply. Text-heavy PDF pages export better as PNG for sharp edges. Photo-heavy pages export better as JPG for smaller file sizes. See our DPI guide for resolution recommendations alongside format choice.