How to calculate your gender pay gap

Steps

On the calculator, choose the rules you report under.
Download the template. Paste your payroll data under its headers, or rename your own columns to match. Names must match exactly, apart from capitals and spaces at the ends.
Save as CSV or .xlsx, with the payroll on one sheet, and choose the file.
Fix anything listed as refused, and choose the file again. The figures and the method appear once it reads cleanly.

What each template needs

UK
Column	What goes in it
employee_id	Your own ID. Each person once.
sex	male or female (or M, F).
full_pay	no if paid at a reduced rate or nil because of leave in the pay period, else yes.
ordinary_pay	Ordinary pay in the pay period, for work in that period.
pay_period_days	7, 14, or 30.44 for a month.
weekly_hours	Your figure under reg. 7. Not needed when full_pay is no.
bonus_in_period	Bonus paid in the pay period, if any.
bonus_period_days	The days that bonus covers: 91.32 for 3 months. Needed when there is a bonus.
bonus_12_months	All bonus in the 12 months to the snapshot date, not prorated.

Ireland
Column	What goes in it
employee_id	Your own ID. Each person once.
sex	male or female (or M, F).
ordinary_pay	12 months, including overtime.
bonus	Bonus in the 12 months, if any.
bonus_period_days	The days that bonus covers: 365 for a year. Needed when there is a bonus.
hours	Working hours in the 12 months: see the Ireland page.
part_time, temporary, benefit_in_kind	yes or no.

Spain
Column	What goes in it
empleado	Your own ID. One line per person and concept.
sexo	hombre or mujer, in full.
grupo	Group, category, level or job.
tipo	base, complemento or extrasalarial.
concepto	The pay concept, as you name it.
importe	Received in the year, with a decimal comma.

EU
Column	What goes in it
employee_id	Your own ID. Each person once.
sex	male, female or non-binary, in full. Single letters are refused: M means mujer in Spain.
category	Your category of workers: same work or work of equal value.
basic_pay	Ordinary basic pay in the year.
variable_pay	Complementary or variable pay in the year.
hours	Paid hours in the year.

Why a row is refused

The calculator never guesses, because a wrong figure can end up published under your name. It lists each cell with its line and reason, and shows no figures until the file reads cleanly. Common reasons:

An amount like 1.500: in one country that is 1,500 and in another 1.5. Write 1500.00, or 1500,00 under the Spanish rules.
A currency symbol, a minus sign or text in a number column.
A sex value outside the template's words, or the same person twice.
Hours of zero or blank, where the hourly figure needs them.

A blank bonus or variable pay cell is read as nothing paid, and the page tells you how many rows that covered. Every other blank is refused.

UK: a record without male or female

The UK figures rest on biological sex, and a Gender Recognition Certificate does not change that, according to the statutory guidance. The guidance says not to single people out, and warns that disclosing this information can be a criminal offence outside the exceptions. Read its route before you change a record. The calculator refuses the row, because the choice is not one a program should make.

Several payrolls

Merge the payrolls of one employer into one file first: each person once, with the same columns. Each legal entity reports for itself, so use one file per entity.

When a figure says "No figure"

A gap needs both men and women in the group, and a men's figure above zero. Without them the page says why instead of showing 0.

Your data

The file is read by a script in this browser tab. It is not uploaded, stored or counted, and closing the tab clears it. The page's security policy allows no connection that could send it, apart from the visit count described in the privacy notice, which never holds your data.

Payroll is personal data and sex is sensitive, so keep the file as carefully as you keep any payroll file.