Reduce image size without losing quality: it's a format decision, not a magic setting
There's no single slider or button that reduces image size without losing quality for every file. What actually works is matching the right format to the right quality setting for your specific image content. A photo, a screenshot, and a line-art logo all compress completely differently, and lossy formats behave nothing like lossless ones.
That's why this tool doesn't push you toward one "best" format. Upload your image above, try a few output formats side by side, and compare the real resulting file size for the picture you actually have — not a generic average.
How the same image compresses across formats
The table below shows typical, well-established compression behavior for each format PhotoConvert supports. These are general tendencies, not guarantees — your actual results depend heavily on what's in the image.
| Format | Type | Typical size vs. original PNG | Best for |
|---|---|---|---|
| PNG | Lossless | Baseline (100%) | Screenshots, line art, and anything needing exact pixels or transparency |
| JPEG (80–85% quality) | Lossy | Often 10–20% of original PNG size | Photos without transparency |
| WebP (80% quality) | Lossy | Often 8–15% of original PNG size, while still supporting transparency | Web use — photos or graphics that need transparency |
| AVIF (80% quality) | Lossy | Often 6–12% of original PNG size — usually the smallest of all | Modern browsers, maximum compression |
| GIF | Lossless, limited to 256 colors | Varies widely | Simple graphics and animation, not photos |
| BMP | Uncompressed | Larger than original PNG | Legacy software compatibility only, never for the web |
| ICO | Varies by embedded size | Small, but capped at 256×256px | Favicons and app icons only |
A worked example
Say you have a 2MB PNG screenshot with mixed text and photo content — a common case for tutorials, documentation, or social sharing images. Converted to JPEG at 85% quality, it typically lands somewhere around 150–300KB. Converted to WebP at 80% quality, it often comes down to roughly 100–200KB, while still letting you keep transparency if the image needs it. Converted to AVIF at 80% quality, it can drop further still, often to around 80–150KB.
Those numbers are typical ranges, not promises — the only way to know for certain is to try it yourself with the tool above and compare the real output size for your specific image.
The quality slider tradeoff
Every lossy format shares the same basic curve. A 90–100% quality setting preserves near-original visual quality with only modest file size savings. The 80–90% range is the sweet spot for most web use — meaningful savings with no visible artifacts for the vast majority of images.
Below 70%, compression artifacts start becoming visible — blockiness around hard edges in JPEG, or blurring and smearing of fine detail in WebP and AVIF. This shows up fastest in high-contrast images and anything containing text, since sharp edges are exactly what aggressive compression struggles to preserve.
That's a real, explainable outcome in certain lossless-format scenarios — not a bug in this tool. Read why did my image get bigger? for the full explanation.
Which format should I pick?
- Web photos: WebP or JPEG
- Graphics or logos needing transparency: WebP or PNG
- Maximum compression for a modern audience: AVIF
- Universal legacy compatibility: JPEG or PNG
- Favicon: ICO — see our PNG to ICO favicon generator
Frequently asked questions
What's the single best format for reducing file size?
There isn't one universal answer — it depends on your image content. AVIF or WebP are usually the smallest for photos, but compatibility with older browsers and whether you need transparency support both matter just as much as raw file size.
Will lowering quality below 80% always look bad?
Not always — it depends heavily on the image. Photos with lots of natural detail and color variation hide compression artifacts well, while screenshots, text, and flat-color graphics show blockiness or blurring much sooner. Test different quality levels with the tool above to see what actually happens to your specific image.
Why did my PNG get bigger when I converted it to another lossless format?
This usually happens when a lossless format has to faithfully store artifacts or noise that were already baked in by an earlier lossy compression step. See our full explanation of why images get bigger after conversion for the details.
Is there a file size limit?
PhotoConvert doesn't impose an artificial file size limit, but image dimensions are capped at 10,000 by 10,000 pixels. Because conversion happens entirely in your browser's memory instead of on a server, very large images are limited by your device's available memory rather than a fixed file size.