There is a minor bug with the calculator at the moment. The “days younger” value should be 365 or less. If it is more than 365 after you have selected your child’s birthday, click the calendar, scroll backward through the months and reselect your child’s birthday. The “days younger” value should be the difference in days between September 1st and your child’s birthday. So, for example, if your child was born on the 4th of October, the “days younger” value should be 33.

To get the most out of this calculator, get your child to take a set of real CSSE 11+ English and maths past papers under exam conditions. Mark the papers and make a note of your child’s English and maths scores out of 60. Select the correct year on the calculator and then input this information. The calculator will give you an idea of what your child’s standardised score would have been had they taken the real paper. You can then view information released by the CSSE for that year showing which scores resulted in offers at CSSE schools.