Staircase dimensions?

[foxhole]

Have used an online calculator to assess what I need for a staircase.
these are the dimensions.
Initial data
Staircase height 2680 mm
Staircase length 2600 mm
Steps amount 12
Steps thickness 22 mm
Steps overhang 5 mm

Stair stringer
Stair stringer length 3733 mm
String cuts spacing 311 mm
Staircase pitch 45.9 °

Steps dimensions
Steps height 223.33 mm
Step depth 221.67 mm
Riser height 201.33 mm
Convenience formula deviation of 6 %,

The dimension I am unsure of is the stringer width, with these dimensions it is around 275mm , is this dimension within the norm. I can reduce/increase width but not sure how much timber is required under each step to maintain overall strength.?
Hope this makes sense.

 

[tony1851]

Your risers are a little high - 220 is usually regarded as a maximum.

 

[foxhole]

Your risers are a little high - 220 is usually regarded as a maximum.

Have adjusted stringer now and now it comes down to 195mm, need as little as possible as stair overhang a doorway on underside, this should leave nothing protruding and give me a neater finish to the under stairs area.
The dimension are not ideal but improvement on what this 30's house had originally, with a 48degree pitch and narrow 200mm steps [and at barely 5' 11" I hit my head if I don't walk down flat footed.]