rpx

You might say

Why does the same button size look wider on another phone?

A relative size unit converted according to a mini program page’s widthWhen page width is 375px, 600rpx is 300px; at 450px it is 360px. Both occupy 80% of page width. Relative sizing does not automatically reflow columns or prevent long text from overflowing.

Know first

WXSS Responsive Design

responsive pixel

How wide is 600rpx on two page widths?

Button size conversionwidth: 600rpx

Page 375px = 750rpx

300px

Share of page width80%

600 ÷ 750 × 375 = 300px

750rpx corresponds to full page width, so 600rpx takes 80%. The diagram encodes that proportion.

How is the size calculated?

Page width is the reference: Displayed CSS pixels = rpx value × page width in CSS pixels ÷ 750. The reference is page width, not physical pixel density.

Keep content readable: Scaling margins and widths can help. Long labels and columns still need wrapping and layout decisions at actual device widths.

Quick checkChoose the best answer

A page grows from 375px to 450px wide. A strip uses width: 750rpx. What happens?

It grows to 450px and still spans the pageIt remains 375px, leaving room beside itIt becomes 750 physical pixels on the display

Send this to the AI Agent in your project

Set this mini program booking button to 600rpx, retaining centering and its label. At page widths of 375px and 450px it should occupy about 80%. Check long labels and landscape too; fix the layout if content overflows or grows too large instead of merely shrinking text.

Learn next

1WXSS→2Responsive Design→

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