Ireland: no standard week in law, and ten public holidays counted separately
Like Britain, Ireland sets no statutory standard week. The Organisation of Working Time Act 1997 caps the average week at 48 hours over a reference period and stops there, so 39 hours is a contract convention rather than a legal figure. It is also the detail most often got wrong when an Irish salary is run through a British or American calculator: the difference between 39 and 40 is about 2.5% on the hourly rate, and between 39 and 37.5 about 4%.
The more useful contrast with Britain is on the other side of the calculation. Ireland's statutory leave is four working weeks, twenty days, and its ten public holidays sit beside them and are counted separately. Britain's is 5.6 weeks, twenty-eight days, but that figure may absorb the bank holidays rather than sitting beside them. Thirty paid days off against twenty-eight, even though the British headline number is the larger of the two.
Irish public holidays also come with a choice the employer makes: a paid day off, an extra day's annual leave, an additional day's pay, or a paid day off within the following month. Whichever is chosen, the day is paid, so the calculator treats all ten as paid time not worked.
There is no statutory overtime premium. Any enhanced rate is contractual, and the only floor is that total pay must stay above the National Minimum Wage across the hours actually worked, which is worth checking against the rate per hour worked shown above if you routinely work unpaid extra hours on a salary.