To design a website using Inkscape, I have added a 960px grid.

But, the first thing I have noticed is that the 14px font seems to big respect to the 960px grid. I expected a smaller font. So.. why does it happen?

Hello

Right now I don't know how to confirm but I think the size of the text it's given in pt (points) units, not in pixel units.

Googling pt to px I found a conversion table:
http://reeddesign.co.uk/test/points-pixels.html

ups... It seems that font size is given in pixels!
http://tavmjong.free.fr/INKSCAPE/MANUAL ... tting.html

... so perhaps you have applied a scale to the text (or Inkscape automatically, because a setup option).
... a quick test in my side, Inkscape says that all is OK.

If you couls attach a sample file... although, on a second tough, the solution may be simple. If you have another program for comparision, export your drawing to it. With the new "measure tool" you can also check the height of your text

What exactly is a problem here?!

14 px large font should mean the distance between baselines at 1× line spacing is 14 pixels.
---Note that by default spacing is set to 1,25---

There is no connection between character size and baseline distances whatsoever.

Although in the digital age of people making and publishing fonts without respect to naming the sizes correctly, professional foundries still use the em or em-square to represent the font size. So a 14px font would have a capital M 14 px wide. It's not always the case, but generally the M is as tall as it is wide.
The baseline separation includes leading, which is something else entirely.

Gleaned from OPs message to the Inkscape User mailing list, the font units can be set in Inks Prefs > Tools > Text. Font units can be point, pixel, pica, mm, cm, inch, and em square (whatever that is ) (and you can check the Tool Tip by mousing over the unit number, to confirm which one is in use, without having to open Inks Prefs)

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