Start with the image’s actual role
A large hero photograph, a small interface icon, and a transparent product image have different requirements. Decide where the image appears, the maximum display dimensions, whether transparency is needed, and which browsers or publishing systems must support it.
Avoid shipping a full-resolution camera image into a small card if a smaller derivative is enough. Keep a master so that you can create a larger version later.
Choose a suitable format
JPEG is widely compatible for photographs without transparency. PNG is useful for transparent graphics and lossless pixel data. WebP and AVIF can offer compact web delivery, but check that the destination supports them and retain fallbacks when your audience or tooling requires them.
Responsive image markup can let a website serve different dimensions to different screen sizes. The source files still need appropriate dimensions and formats; conversion alone does not create a responsive implementation.
Resize and compress
Resize an image to the largest dimensions needed in its layout, then compare a few reasonable compression settings. Lower lossy quality may reduce file size but can make edges or textures look worse. Use visual comparison rather than an arbitrary target size.
Pixuna’s Image Resizer lets you set a width, height, or ratio-preserving box. Its Format Optimizer exports JPEG, WebP, or AVIF and may scale dimensions above 2,000 pixels. The Image Compressor has a fixed JPEG output and may scale wide images to 1,200 pixels.
Measure the published result
Check the output file’s dimensions and byte size, then test it in the page or product where it will be used. Compare visual quality at normal display size and confirm that transparent regions and colors remain acceptable.
A smaller source image can reduce transfer size, but total page performance also depends on layout, caching, network conditions, scripts, and other assets. Measure the deployed page rather than assuming that one optimized image fixes every performance issue.
A simple Pixuna workflow
Use Image Resizer to reduce oversized dimensions, then use Format Optimizer or Image Compressor to create an output. Use the Image Converter if a particular format is required. These image tools process files in the browser.