概述
本指南比较了PNG和SVG在最重要的标准下，以帮助您选择适合您需求的格式。
SVG是矢量图，能够无限缩放；PNG是栅格图，最适合复杂图像。
Head-to-Head Comparison
可缩放性
PNG: PNG在超出其原始分辨率时会变得模糊。
SVG: SVG可以完美缩放到任何大小而不会失去质量。
Winner: SVG
文件大小
PNG: 对于简单图形，PNG较大，但对于复杂图像与SVG相似。
SVG: SVG对于简单图形（标志、图标）非常小，但对于复杂插图则较大。
Winner: 平局
使用场景
PNG: PNG最适合用于照片和颜色丰富的复杂图像。
SVG: SVG最适合用于标志、图标、插图以及任何需要缩放的内容。
Winner: 平局
可编辑性
PNG: PNG像素无法在没有图像编辑器的情况下单独编辑。
SVG: SVG 路径可以通过文本编辑器或矢量工具轻松编辑。
Winner: SVG
网页支持
PNG: PNG 在每个浏览器中都得到普遍支持。
SVG: SVG 得到所有现代浏览器的支持。
Winner: 平局
Raster Versus Vector
The core distinction is raster versus vector. PNG stores an explicit grid of pixels, compressed losslessly with DEFLATE and per-row prediction filters, so the file describes exact color values at a fixed resolution.[1][2] SVG instead describes an image as XML instructions, paths, shapes, text, and gradients, that a renderer draws on demand.[3] Because SVG is a mathematical description rather than a pixel array, it has no inherent resolution.
Scaling and Fidelity
An SVG can be scaled to any size and remains perfectly sharp, since its shapes are recomputed at the target resolution.[4] A PNG becomes blurry or blocky when enlarged beyond its native pixel dimensions, because the renderer must interpolate pixels that were never stored. Conversely, SVG is impractical for photographs: representing millions of subtly varying pixels as vector primitives produces enormous, inefficient files, whereas PNG handles complex per-pixel detail naturally.[1]
File Size Behavior
The two formats scale oppositely with content. An SVG's size depends on the number of shapes it contains, not on its display dimensions, so a simple logo stays tiny whether shown at icon size or on a billboard.[3] A PNG's size depends on its pixel dimensions and visual complexity; doubling its width and height roughly quadruples the pixel count. For simple graphics, SVG is usually far smaller; for detailed raster imagery, PNG is more efficient.
Editability and Interactivity
Because SVG is text-based XML, it can be edited in a code editor, styled with CSS, animated, scripted, and searched, and its individual elements remain addressable.[3] PNG is an opaque pixel array that can only be edited as an image. Both support transparency: PNG through an alpha channel, SVG inherently, since unpainted areas are simply not drawn.[2]
Standardization and Applications
PNG is defined by the W3C and IETF (RFC 2083) and ISO/IEC 15948; SVG is a W3C standard.[1][2][3] SVG is used for logos, icons, charts, and line art that must scale across screen sizes, while PNG is used for screenshots, detailed graphics, and raster artwork requiring lossless pixels and transparency.[4] Both are supported by all major browsers.