Day 1 schedules

Plan without dates. Every day counts from Day 1, so you can sketch how long a project might take before anyone knows when it starts.

Sometimes you need to say "this project might take nine months" before there's a start date, for a proposal or an early look at a project. A Day 1 schedule does that. It has no calendar dates. The project always starts on Day 1, and everything else counts from there.

Turn it on #

In the scheme bar, click Dates ▾ and pick Day 1. The button then reads Day 1 ▾.

Your tasks, durations and dependencies stay as they were. Only the way days are shown changes.

What changes on Day 1 #

Days show as Day N. Start and end columns, the side panel, tooltips and the change log all read Day 12 instead of a date. To pin a start, type a number (12) or Day 12.
The Gantt counts from Day 1. The header shows Month 1, Month 2, and the week marks read Wk 1, Wk 2.
The plan's length shows next to the project window, for example 40 weeks (about 9.2 months). It runs from Day 1 to the last task.
No holidays. There are no dates for holidays to fall on. In business-day mode weekends still count as days off, so a 5-day task takes one week. Turn Business days off to count every day.
No today. The today line, look-ahead filters and the Calendar view are off. In the Gantt, the Day 1 button scrolls back to the start.
Exports. The spreadsheet and PDF show Day N. There's no Outlook (.ics) export, and a live link's calendar feed stays empty.

Switch to real dates #

When you know the start, click Day 1 ▾, choose the date Day 1 lands on, and click Use real dates. The whole plan slides to that date. Every pinned start, the project end and any actual dates move by the same amount. Holidays apply again, so some dates may move a day or two to step around them.

You can switch back to Day 1 at any time. Nothing is lost going either way.

Good to know #

A Day 1 schedule works with everything else: dependencies, lags, steps, groups, codes, the critical path, snapshots and comparisons.
The change log records the switch as one line, for example Switched to real dates — Day 1 is 2027-03-01.
An AI assistant connected to your account sees Day 1 schedules in Day N too. See the AI connector.