PNG vs JPG: Which Image Format Should You Use?

Choosing between PNG and JPG is one of the most fundamental decisions you make when preparing images for the web, print, or storage. These two formats have coexisted for decades, and while they may seem interchangeable at a glance, they are built on entirely different compression philosophies that make each one suited to specific kinds of content. Pick the wrong one and you either end up with a file ten times larger than it needs to be, or a photograph that looks like it was left out in the rain. In this guide we break down exactly how each format works, where each one shines, and how to decide between them in every common scenario.

The Core Difference: Lossless vs Lossy

The single most important distinction between PNG and JPG is the way each format handles compression. Everything else flows from this one design choice.

PNG uses lossless compression. When you save an image as a PNG, every single pixel that was in the original is preserved in the file. The compression algorithm finds repeated patterns and encodes them efficiently, but no pixel data is ever discarded. This means a PNG always looks exactly like the source, no matter how many times you save it.

JPG (sometimes written JPEG) uses lossy compression. When you save a JPG, the algorithm throws away visual information that the human eye is less likely to notice — subtle color variations, fine detail in smooth areas, high-frequency noise. The amount of information discarded is controlled by a quality setting, typically ranging from 1 to 100. A quality of 90 keeps most of the detail; a quality of 30 produces a much smaller file but introduces visible artifacts.

Why This Matters

The lossless vs lossy distinction has two practical consequences:

1. File size: For the same image, a PNG is almost always larger than a JPG, often by a factor of 5 to 20. A photograph that is 200 KB as a JPG might be 1.5 MB as a PNG.
2. Generation loss: Every time you re-save a JPG, more information is lost. Open a JPG, edit it, and save it again, and the quality degrades further. PNG does not have this problem — you can re-save it as many times as you like with no loss.

When to Use PNG

PNG is the right choice in several specific situations. Once you internalize these, the decision becomes almost automatic.

Screenshots and UI Captures

Screenshots of user interfaces, application windows, code editors, and websites are almost always best saved as PNG. The reason is that UI elements contain sharp edges, solid blocks of color, and text — exactly the kind of content where JPG artifacts are most visible. A screenshot saved as a low-quality JPG will show ugly ringing around text and blocky bands across what should be smooth color areas. PNG preserves every edge cleanly.

Graphics with Transparency

PNG supports an alpha channel, which means pixels can be partially or fully transparent. This is essential for logos, icons, badges, and any graphic that needs to sit on top of a varying background. JPG has no transparency support at all — a JPG always fills every pixel with some color, typically white if you do not specify otherwise.

Images with Text

Any image that contains crisp text — infographics, diagrams, annotated screenshots, posters with typography — should be saved as PNG. JPG compression smears text edges and introduces a "dirty" look around letters that is immediately noticeable to most viewers.

Line Art and Flat Color Graphics

Illustrations with large areas of solid color, line drawings, and flat-design graphics compress extremely well as PNG and look perfectly clean. The same graphics saved as JPG often show banding and blocky artifacts in the solid color regions.

When to Use JPG

JPG is the right choice for photographs and other continuous-tone images.

Photographs

Photographs are what JPG was designed for. Natural scenes contain subtle gradients, millions of colors, and fine texture detail that the human eye perceives as smooth transitions. JPG's lossy algorithm is tuned to discard exactly the kind of information that is least noticeable in photographic content. A well-compressed JPG at quality 80 to 85 is visually indistinguishable from the original for most photographs, yet a fraction of the file size.

Large Web Images

For hero images, full-width banners, and any large photographic content on a website, JPG is almost always the right call. The file size savings directly translate to faster page loads, which improves user experience and search rankings.

Email Attachments

When you embed images in emails, file size matters more than ever. Many email clients block or delay large images. A JPG keeps attachments small enough to load reliably across all clients and devices.

The Compression Tradeoff in Numbers

To make this concrete, here is what you can typically expect when saving the same 1920 by 1080 photograph in both formats:

• PNG (24-bit): roughly 3 to 5 MB, depending on the content.
• JPG at quality 90: roughly 400 to 700 KB.
• JPG at quality 75: roughly 150 to 300 KB.
• JPG at quality 50: roughly 80 to 150 KB, with visible artifacts.

For a screenshot of a text-heavy application window, the comparison flips:

• PNG: roughly 200 to 400 KB.
• JPG at quality 85: roughly 150 to 300 KB, but with visible text artifacts.
• JPG at quality 60: roughly 80 KB, with severe artifacts around text.

Notice that for the screenshot, the PNG is not much larger than the JPG, and the JPG introduces quality problems. This is why PNG wins for screenshots even though it is a lossless format.

Color Depth and Other Technical Differences

Beyond compression, there are a few other technical distinctions worth knowing.

Color Depth

• PNG supports 8-bit palette images (up to 256 colors), 24-bit truecolor (about 16.7 million colors), and 32-bit truecolor with an alpha channel. It also supports 48-bit and 64-bit high bit depth modes for specialized workflows.
• JPG supports 24-bit truecolor and 8-bit grayscale. It does not support palette images, transparency, or alpha channels.

Metadata

Both formats support EXIF metadata (camera settings, GPS coordinates, timestamps), but PNG's metadata support is more flexible through its chunk-based architecture. JPG uses the more standardized EXIF and IPTC blocks that most photo management tools read natively.

Progressive Rendering

JPG supports progressive encoding, where the image loads in coarse passes that refine over time. This gives a blurred preview that sharpens, which feels faster on slow connections. PNG supports a similar feature called interlacing (Adam7), but it is less efficient and less widely used.

Common Mistakes to Avoid

Saving a Photo as PNG for the Web

This is the most common mistake. A 2 MB PNG of a photo on your website adds seconds to your page load for no visual benefit. Convert it to a JPG at quality 80 and it becomes 200 KB with no perceptible quality loss.

Re-Saving JPGs Repeatedly

Every time you open, edit, and re-save a JPG, you lose quality. If you are doing multiple rounds of editing, keep a lossless master (PNG or a raw format) and only export to JPG as the final step.

Using JPG for Logos

A logo saved as JPG will have a visible white or colored rectangle behind it wherever it should be transparent, and the edges of the logo will show compression artifacts. Always save logos as PNG with transparency.

Using a Single Quality Setting for Everything

Quality 85 is a good default for most photographs, but some images (those with lots of fine detail or smooth gradients) need higher quality, while others (busy, textured scenes) can go lower without visible problems. Test a few quality levels and pick the smallest one that looks acceptable.

A Simple Decision Framework

If you want a quick rule of thumb, ask yourself two questions:

1. Is the image a photograph? If yes, use JPG.
2. Does the image need transparency, contain text, or show sharp UI elements? If yes, use PNG.

If the answer to both is no — for example, a flat illustration with no text and no transparency — either format works, but PNG will usually look cleaner and JPG will usually be smaller. Pick based on whether file size or visual fidelity matters more for that specific use.

The Modern Alternative: WebP and AVIF

It is worth noting that in 2026, you often do not have to choose between PNG and JPG at all. The WebP format supports both lossy and lossless compression, plus transparency, and typically produces files 25 to 35 percent smaller than comparable PNGs and JPGs. AVIF goes further, offering even better compression. If your platform supports these modern formats — and virtually all modern browsers do — they are often a better choice than either PNG or JPG. We cover WebP and AVIF in detail in separate guides.

Conclusion

PNG and JPG are not competitors so much as complements. PNG is the precision tool for graphics, screenshots, text, and anything that needs transparency or pixel-perfect reproduction. JPG is the efficiency tool for photographs and large continuous-tone images where small file size matters more than pixel-level accuracy. Use each for what it was designed for, keep a lossless master for anything you plan to edit again, and your images will look better and load faster.