How do you calculate gross salary from net?

From net to gross

Almost everyone knows their net salary, the amount that lands in the account at the end of the month. But there are situations where you need the gross: to negotiate a raise, to answer a job offer that asked you for a net figure, or to compare offers. The question then runs the other way round from usual: what gross salary do I need to take home this net?

That is exactly the calculation this page explains and that the gross salary calculator does for you.

The net-salary calculation, in reverse

The net-salary calculator goes from gross to net: it takes the gross salary and removes Social Security and IRS. Gross salary does the reverse journey, from net to gross.

The important difference is that there is no direct formula. Social Security is a flat rate, but IRS rises in brackets¹: the more you earn, the higher the rate applied to the next slice of income. So the relationship between gross and net is not a simple percentage. The calculator solves the problem by approximation: it looks for the gross salary whose net matches the figure you entered. Because it uses the same engine as the net-salary calculator, the two results fit together: the gross you get here returns exactly your net in the other calculator.

What is taken from the gross salary

Two mandatory deductions come off the gross salary before it reaches your pocket:

IRS is not charged on the whole gross: first the Category A specific deduction is removed (article 25 of the CIRS²), and only then are the article 68 brackets applied to what is left. What remains of the gross, after Social Security and IRS, is the net.

Example: what gross gives €1,154.98 net?

Say you want to take home €1,154.98 net per month, with salary paid 14 times a year (the 12 months plus the holiday and Christmas bonuses). The calculator looks for the gross whose net gives that figure and returns €1,500 per month. The check, step by step:

€1,500 × 14 = €21,000 a year

Social Security: 11% of 21,000 = €2,310

IRS on the 2026 brackets over the taxable income = €2,520.28

Net: 21,000 − 2,310 − 2,520.28 = €16,169.72 a year, that is €1,154.98 per month

Exactly the net requested. That is why the calculator picked €1,500 of gross.

Why the result changes between 14 and 12 payments

In Portugal salary is usually paid 14 times a year. But you can choose 12 payments when the bonuses are paid in twelfths (spread across the months) or simply do not apply.

The choice is not neutral: it changes the total annual income and, with it, the bracketed IRS. So for the same monthly net, the gross salary needed is not the same with 14 or with 12 payments. Always use the option that matches your contract.

It is an estimate of the base gross

The figure the calculator returns is the base gross salary that, as a rule, produces the net you entered. Like the net-salary calculator, it does not include:

• the minimum-existence floor, which protects the lowest incomes;
• dependants and deductions to tax (health, education, invoices);
• IRS Jovem and other special regimes.

All of these lower the real IRS. When they apply, the true gross is equal to or a little lower than the estimate, especially for net pay near the minimum wage, where the real IRS is often close to zero. Always check your payslip.

And for negotiating a salary?

If you already know the net you want to take home, this calculation gives you a solid starting point for the conversation: the gross to ask for. Bear in mind the employer thinks in terms of the gross and the total cost including the company Social Security (which is added on top of your salary), and that the final figure depends on your personal deductions. To understand the way back, from gross to what you receive in hand, see how net salary is calculated and the IRS withholding month by month.