Question

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Difference of px, dp, dip and sp in android

I am new to Android and I was trying out this tutorial

In that tutorial, they used the unit “sp” for textSize attribute and “dp” for other attributes.

Please tell me how sp differs from dp?

Answer 1

The dp has constant ratio transition to px: dp = px * ratio. Where ratio will never change on any particular device.

While sp (s for scaled) has scalable ratio: sp = px * ratio * scale. Where ratio never changes, but scale is user configurable. This scale can be used by people who need larger font sizes, for example, to use device more comfortably.