Image File Formats Explained: JPEG, PNG, WebP, HEIC, SVG
August 16, 2026· 3 min read
There are five image formats you'll actually meet in the wild: JPEG, PNG, WebP, HEIC, and SVG. They look similar at a glance and behave completely differently underneath. This guide explains each one in plain English — and points to a deeper article for each.
The quick overview
| Format | Compression | Transparency | Animation | Best for |
|---|---|---|---|---|
| JPEG/JPG | Lossy | No | No | Photos, web, print |
| PNG | Lossless | Yes | No | Graphics, screenshots, logos |
| WebP | Both | Yes | Yes | Modern web images |
| HEIC | Lossy (very efficient) | No | No | Apple photo storage |
| SVG | Vector (math) | Yes | Yes (CSS/SMIL) | Logos, icons, illustrations |
JPEG (JPG): the universal photo format
Lossy compression, universally supported, ideal for photos. The trade-off: re-saving a JPEG repeatedly degrades it. Best for photos on the web, in email, and in print.
PNG: the lossless workhorse
Lossless, supports transparency, terrible at compressing photos. Best for screenshots with text, UI graphics, and anything you'll edit repeatedly. Transparency makes it irreplaceable for logos on colored backgrounds.
WebP: the modern web format
Smaller than JPEG and PNG at the same quality, supports transparency and animation. Every modern browser supports it. Best for website images where every kilobyte matters.
HEIC: Apple's space saver
Default on iPhones, roughly half the size of JPEG at the same quality. The catch: compatibility. Windows needs an extension, many websites and apps reject it. Best kept inside Apple's ecosystem; convert to JPG before sharing. See HEIC vs JPG.
SVG: the image that isn't pixels
Not a raster at all — SVG is math (coordinates and curves), so it scales to any size without blur. Best for logos, icons, and illustrations. It can't represent photos, and you often need a PNG version for platforms that reject SVG. See SVG vs PNG.
How to choose: a simple decision flow
- Is it a photo? → JPEG (or WebP on the web)
- Is it a logo/icon/illustration? → SVG (vector) or PNG (raster)
- Is it a screenshot? → PNG
- Is it for a website? → WebP
- Is it an iPhone photo going somewhere outside Apple? → Convert HEIC to JPG
Converting between formats
The Image Converter on SlimImg handles JPEG, PNG, and WebP in either direction — in your browser, no uploads:
- WebP to JPG — for compatibility
- PNG to JPG — for smaller photos
- JPG to PNG — for editing workflows
- WebP vs PNG — the full comparison
For Apple photos, use the HEIC to JPG converter; for vectors, the SVG to PNG converter.
Frequently asked questions
Which format has the best quality?
Lossless formats (PNG, SVG) preserve everything, but "best" depends on the image: photos look great as high-quality JPEG or WebP, while text and graphics need lossless formats to stay sharp.
Which format is smallest?
For photos: WebP. For simple graphics: SVG. For everything else, it depends on the content — that's why conversion guides always mention file size trade-offs.
Do I need to understand formats as a beginner?
Just learn one rule: photos → JPEG/WebP, graphics → PNG/SVG, Apple sharing → convert HEIC to JPG. Everything else is refinement.
What should I do with my image once the format is right?
Resize and compress it — the image compression guide shows how to keep quality while shrinking files.
Can one tool handle all these conversions?
Yes — the Image Converter converts between JPEG, PNG, and WebP in your browser, and the HEIC and SVG converters sit right alongside it on SlimImg.
The bottom line
Match the format to the job: JPEG/WebP for photos, PNG for graphics, SVG for scalable logos, and JPG for anything Apple sends elsewhere. Keep this guide — and the Image Converter — handy for every switch.
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