A focus block is not a to-do item with a time attached. It is a meeting you hold with yourself, and like any meeting it survives only if the people who book your day can see it, respect it, and cannot quietly overwrite it. Google Calendar, Outlook and Apple Calendar each handle this differently, so the paths below are named per platform rather than described in general.
Pick the block length from the work, not from a blog post
Ninety minutes suits writing, debugging and design, because that is roughly how long it takes to reach the point where a problem starts to give. Twenty-five suits admin, email triage and code review, where the task is already defined and the only risk is drift. Forty-five minutes is a compromise that fits neither: too short to get deep, too long to stay sharp on chores.
Count the week before blocking any of it. If twelve of your forty hours are already meetings, you can defend eight to ten hours of focus, not twenty-five. Booking twenty-five and keeping four teaches you to ignore your own calendar, which is worse than booking nothing at all.
Create the block so colleagues can see and respect it
Google Calendar (work or school accounts): click and drag across the slot, then choose Focus time at the top of the event card instead of “Event”. That changes the icon to headphones, mutes Chat notifications and adds an “Automatically decline meetings” checkbox. Two limits catch people out: focus time can only be created from Day or Week view, and it must have a fixed start and end time. Personal Gmail accounts do not get the event type — use an ordinary event titled “Focus — no bookings” with visibility set to Busy.
Outlook: the new Outlook has a Focus event type, and Microsoft Viva Insights can book focus time automatically around your existing meetings from the Insights pane. Without either, create a normal appointment, set Show as: Busy, and enable declining of conflicting invites under Settings → Calendar → Events and invitations.
Apple Calendar: there is no focus event type. Make a separate calendar called Focus, give it a colour you never use elsewhere, turn its alerts off in Settings → Alerts, and select that calendar in a macOS or iOS Focus mode so only its events stay visible.
Two conventions do more than any menu setting: put “no bookings” in the event title, and fill the location field with “deep work” so the block reads as deliberate when someone glances at your day.
Defend the edges of the block
Blocks are lost at their boundaries far more often than in the middle.
- Leave ten minutes after every cluster of meetings. Back-to-back calls push the next block later until it vanishes.
- In Google Calendar enable Speedy meetings under Settings → General, so 30-minute meetings end at :25 and hour-long ones at :50.
- Fill in Working hours & location, so nobody books you at 21:00 and your blocks stay inside the part of the day you can actually work.
- Silence chat for the duration rather than relying on willpower — Focus assist on Windows (Settings → System → Focus assist) or a macOS Focus mode with only one person allowed through.
- Never book the first thirty minutes of the day. It is where everything urgent lands by default.
Check whether the blocks are actually working
Google Workspace accounts get Time insights in the left sidebar of Calendar, which reports meeting hours per week and shows which blocks were declined or moved. Outlook users get similar numbers from Viva Insights under meeting habits and focus-time adoption. On a personal account, count by hand: at the end of each week, write down how many blocks survived intact. Fewer than half means the slot is wrong — usually too early, or placed immediately before a recurring stand-up.
Change one variable per week. Moving a ninety-minute block from 09:00 to 14:00 is a testable change; rebuilding the whole system every Monday is theatre.
What to do when a block gets eaten anyway
It will get eaten. The recovery rule matters more than the block: when one is lost, do not push it into the evening. Reschedule it inside the same week and delete something else from the calendar to make room, otherwise the block becomes extra work stacked on top of the work it was supposed to protect. If a recurring meeting eats the same slot three weeks running, that is a scheduling negotiation, not a calendar problem — move the block permanently rather than defending it weekly.
Pair this with a fixed start to the morning — our morning routine guide covers the twenty minutes before the first block — and with these habits for cutting screen time, since a focus block is only as good as the notifications you let into it. If the inbox is the thing that keeps breaking through, the 15-minute inbox system is the prerequisite. Google documents the event type at Use focus time in Google Calendar.