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"It's on confidence that we must act", Najat Vallaud-Belkacem, the newly appointed minister for women's rights, city, youth and sports told Le Parisien newspaper on Monday.
The app will offer all women the "tools that were until now the prerogative of senior executives belonging to networks from the Grandes Ecoles" the minister added, referring to France's elite universities.
She described the app as "coaching for all women."
Men are nine times more likely to ask for a pay rise than women. Self-confidence, can explain up to 4.5 percentage points of the 25 percentage point wage gap between men and women, the French government says.
Women who download the app will first have to fill in a quick questionnaire, in which they'll be asked, among other things, what their reaction to a male colleague's derogatory comments in a meeting would be in order to gauge their self-confidence.
Depending on their answers, they will be presented with advice and videos on sexism, wage negotiation, how to succeed in an interview or in managing a team.
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But the app also includes a wage calculator so that women can measure whether the gap between their salary and the pay of male colleagues is within the national average. By comparing themselves to men, the minister said, women will be able to "realize their value."
One aspect that makes the fight for equal pay harder is the wide variety of statistics on the matter. European Commission research shows that women earn on average 16.4 percent less than men across the EU. In France, men on average earn 14.8 percent more than women, the commission says – at odds with the French calculations. Meanwhile, in Germany, the figure stands at 8.6 percent and 15.9 percent in Sweden.
However, according to the Business and Professional Women Federation, which first launched the Equal Pay Day initiative, France lags many of its neighbors with its pay gap reaching 28 percent.
It estimates that the pay gap in Sweden is of 13.9 percent, while it would reach 22 percent in Germany.
The figures differ widely because the methods used to measure the pay gap are different. In the case of France, BPW told CNBC by phone that the results were based on figures previously released by the French national statistical agency Insee who calculated the difference in annual salary between women and men in the private sector only. However, Eurostats who compiled the figures for the European Commission takes into account the average gross hourly earnings, which does not necessarily reflect imposed part-time work, more regular among women than men.
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