Calculation of income tax after a job change

[FuzzyLogic]

Until August this year I was working for company 'A'. I then moved to company 'B'. In the process of moving to company B, I took a good pay rise, however I am not sure my PAYE tax deduction is now correct.

Please can someone explain the correct method for manually working out what I should be paying. Most of the online calculators I have found assume a flat income for a year.

Thanks.

[FredClogs]

The online PAYE calculators should be accurate in showing what you are paying now based on your salary now, what you were paying before should have no bearing. The only thing that may have a bearing is if you've been put on a temporary tax code because your P45 hasn't be processed.