W3C home > Mailing lists > Public > w3c-wai-ig@w3.org > January to March 2002

Re: Measuring in Pixels

From: Andrew McFarland <andrew.mcfarland@unite.net>
Date: Wed, 13 Mar 2002 08:37:40 +0000
Message-Id: <>
To: "WAI (E-mail)" <w3c-wai-ig@w3.org>
At 12:42 11/03/2002 -0500, RUST Randal wrote:
>When you measure something, you stick to one type of unit.  Be it inches or
>centimeters.  You don't mix the two, because it's not logical.
>So why is it that we mix them on the web?  We set our screen resolution to
>pixels.  Yet we have all of these other measurements such as points, ems and
>percentages that screw things up.

We set screen resolution in pixels. because pixels relate to the physical 
properties of our hardware. We also need to specify the number of pixels 
per inch. That way we can set the physical resolution to work well with the 
hardware, but set the logical resolution to something that works well with 
our eyes. Setting measurements in pixels ignores the second step. Sometimes 
you can olny specify in pixels though (when dealing with rasterized 
graphics, for example).

The question "How does this site look at 800 by 600" is actually 
meaningless. You need to specify the pixels per inch as well.


Andrew McFarland
UNITE Solutions
Received on Wednesday, 13 March 2002 03:39:22 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 20:36:07 UTC