I'll develop a work experience calculator for pension end-to-end

I develop work experience calculators for legal consultation websites — a tool that calculates not future pension, but work experience itself: how many years, months, and days a person actually worked across all jobs, accounting for gaps between them. This is a separate task from a pension calculator, and I build the module specifically as an experience counter, not as a financial income forecast tool for retirement.

A visitor adds any number of periods: for each they specify the workplace, hire date and termination date, and if needed — special working conditions, maternity leave, or other significant intervals. The calculator sums all periods, correctly handles date overlaps and gaps between jobs, and outputs the total experience in a clear format: years, months, days.

Development includes an input form with rows that add and delete without page reload, date validation, server-side calculation logic, and a printable certificate version.

What is included in the package:
— form with dynamic adding and removing of work periods;
— total experience calculation accounting for gaps and date overlaps;
— responsive layout for mobile devices;
— testing on edge cases: incomplete months, disputed termination dates.