What is the normal blood pressure for an 8 year old child?

To calculate this, you must know your child's height centile. This can be obtained from charts available on the internet or from your local family doctor. Contact me privately if you wish to have this centile calculated.

You must then use this table to calculate the average blood pressure for your child.

http://www.nhlbi.nih.gov/guidelines/hypertension/child_tbl.pdf

If you look on the left hand side, where it says BP percentile, the 50th percentile is what 50 out of 100 children will have as their BP, 95 is the top 5 highest out of 100 children etc.