Employment Milestones Guide

A probation period is a fixed window after joining during which either party can typically end employment with shorter notice, and during which performance is formally reviewed. Three months and six months are the most common lengths; some contracts use 90 calendar days or 12 months instead.

Probation almost always counts forward from the joining date, using the same include-start-date and calendar-vs-business-day rules as a notice period. The difference is the anchor: probation starts at joining, not at a resignation or termination notice.

Use the Probation End Date Calculator with the joining date and probation length to get the exact review date. If the joining date falls at month-end, month-based probation lengths clamp to the end of the target month—joining on 31 August with a three-month probation ends 30 November, not 31 November.

Length of service is the calendar span from a joining date to either today (for current employees) or a last day of employment (for former employees), expressed in years, months, and days rather than a rounded year count.

Tenure thresholds appear throughout HR policy: statutory redundancy pay often requires a minimum length of service, service awards trigger at five-, ten-, or twenty-year marks, and pension or equity vesting can depend on completing a specific tenure milestone to the day.

The Employment Duration Calculator uses the same date-span engine as the Age Calculator, so leap years and month-length differences are handled the same way. Include- or exclude-boundary settings matter most when a policy's tenure threshold is close to the calculated result—being one day short of a five-year mark can change eligibility.

When an offer states a gap from a previous role's last working day—rather than a fixed calendar date—the new joining date has to be calculated and then checked against weekends and holidays, since no one starts a new role on a Saturday.

The Joining Date Calculator adds the stated gap (in calendar or business days) to the previous last working day, then shifts the result onto the nearest working day in the chosen direction if it lands on a non-working day. This mirrors the working-day adjustment used by the Last Working Day Calculator, but applied forward instead of backward.

Calendar-day and business-day gaps produce different results for the same stated length: a five-calendar-day gap from a Friday can land midweek, while a five-business-day gap from the same Friday lands on the following Friday because weekends are skipped during the count.

A retirement date is the calendar date on which a person reaches a target age, calculated by adding whole years to a date of birth. Unlike notice periods or probation, retirement dates are age-based rather than length-based—the input is a birth date and a target age, not a start date and a duration.

Retirement age is not one number. State or national pension age, an employer scheme's normal retirement age, and an individual's personal target can all differ, and each is worth calculating separately for comparison. Some pension schemes also allow early access from a lower minimum age.

The Retirement Date Calculator adds the target age to the date of birth, reports current age alongside it, and shows time remaining until the target date—or time elapsed, if the date has already passed. 29 February birthdays resolve to 28 February in non-leap years, matching standard administrative practice.

Starting from a known date and adding a length forward: use the Probation End Date Calculator (joining date + probation length) or the Notice Period Calculator (notice start + notice length).

Working backward from a target date: use the Resignation Notice Calculator (target last working day → resignation deadline).

Measuring the span between two known dates: use the Employment Duration Calculator (joining date → today or a last day).

Adding a gap and checking for a working day: use the Joining Date Calculator (last working day + gap, adjusted forward) or the Last Working Day Calculator (notice end date, adjusted backward or forward).

Adding years to a birth date: use the Retirement Date Calculator.