Google announced Gemini in Sheets for iOS on October 19, 2026, with a gradual rollout that began October 15. It supports questions and analysis for eligible accounts; this is not a claim that every Excel function or automated edit is available in the mobile interface. If you turn an AI answer into an Excel date formula, define the calendar explicitly and verify it in the destination workbook. The example below uses Excel’s English function notation.
“Add five working days” is incomplete unless the working calendar is defined. Tell the AI which days are weekends, whether the start day counts and which holiday list your calculation should use.
Give the formula explicit inputs
Excel’s WORKDAY.INTL supports custom weekends and a supplied holiday range. In an English-function example, =WORKDAY.INTL(A2,1,1,H2:H10) advances one workday from the date in A2, using Saturday and Sunday as weekends and the dates in H2:H10 as holidays. Function names and argument separators vary by locale.
Use a Friday start: without a holiday, the next workday is Monday. Put that Monday in the holiday range and the expected result becomes Tuesday. Ensure the cells contain real dates, not text that merely looks like a date.
Check the calendar’s authority
An AI-generated formula does not know every regional closure or your organization’s schedule. Keep the holiday list sourced and maintained. This verifies date arithmetic, not a legal deadline or a guaranteed delivery date.
For a dated sample, put Friday, October 23, 2026 in A2. One workday later is Monday, October 26. Mark October 26 as a fictional nonworking day in the test holiday list, and the expected result is Tuesday, October 27. This invented calendar tests the formula; it is not a statement about a country’s actual holidays.