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Wondering what size your image will be after compression? Set format and quality, then get a realistic estimate before you export.
Or enter dimensions below for a quick estimate
Enter width and height—or upload a photo to pull real dimensions automatically.
Choose output format (JPG, PNG, or WebP) and move the quality slider to match your delivery target.
See estimated file size before you compress, then jump to our compressors or desktop app to process for real.
Wondering what size your image will be after compression? Set format and quality, then get a realistic estimate before you export.
Check whether your image will fit under attachment or upload limits before sending.
Preview output weights for hero banners and product shots at target dimensions.
Compare quality settings side by side to pick the smallest file that still looks great.
File size depends on pixel count, format, and encoder settings. A 4000×3000 JPEG at 95% quality can be several megabytes; the same scene at 1080px wide and 80% quality might be under 200 KB.
This calculator helps you plan before you commit—useful for email limits, CMS upload caps, and performance budgets on marketing landing pages.
Different formats behave differently. PNG is lossless and larger for photos but ideal for graphics with transparency. WebP often beats JPEG on photos at the same perceived quality. JPG remains the safest default for compatibility.
Toggle formats and quality in the tool to see how each choice affects estimated weight at your target resolution.
Once you know your target dimensions and quality, use our free JPG, PNG, and WebP compressors for one-off files. Teams processing hundreds of assets per week benefit from the desktop app's batch queues and Pro metadata presets.
Combine this calculator with the image resizer when you need to hit both pixel dimensions and byte budgets in one workflow.
Common questions about using our free image file size calculator tool.
The online tool is great for quick one-offs. For bulk batches, folder watch mode, and full privacy — the desktop app is built for that. Free to try. $19 once to go unlimited.
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