The short version: Vertex42's free "World Meeting Planner" Excel template is a genuinely popular manual workaround, enter up to 7 locations' offsets, then eyeball a grid for overlap. It works, and it's free, but every team change and every daylight-saving shift needs a manual update, and it never suggests a specific time or books anything, that part is still entirely on you.
If you've never built one yourself, there's a good chance someone on your team has: a spreadsheet with a column per city, rows for hours of the day, and a manually-maintained grid for spotting the overlap. It's common enough that a free, dedicated template exists just for this.
How the manual spreadsheet actually works
Vertex42's "World Meeting Planner" template asks you to enter up to 7 locations along with their UTC offset and whether they observe daylight saving. It then lays out a grid you read by eye to spot where everyone's normal daytime hours line up. It's a genuinely well-built tool for what it is, free, works offline, no account, and it's popular enough to be one of the most widely shared templates on Vertex42's whole site, itself a signal that plenty of people reach for a spreadsheet before anything else, long before they ever consider a dedicated app for the job.
Where the manual approach breaks down
Three things need constant upkeep: adding or removing teammates as the roster changes, updating the DST flag twice a year per location, and rereading the grid every time you actually need to book something, since the spreadsheet only shows the static picture, not a specific recommended time. None of that is hard on any single occasion, it's the repetition that adds up, the same manual check every week, for every meeting, forever.
The moment you save it, it starts drifting out of date, a new hire, a changed schedule, an upcoming clock change. That's the exact gap between a manual grid and something that stays live automatically, and it's a gap that widens every week nobody goes back to update the file.
The automatic version
Atlas is the same underlying idea, seeing where a distributed team's hours overlap, but live instead of static. Add a teammate once and their city, working hours and DST rules stay current automatically. The map shades the real overlap for you, auto-suggests the best specific meeting time, and books it to your calendar in one tap. No grid to reread, no manual DST updates twice a year.
So which should you use?
The Vertex42 spreadsheet is a genuinely fine choice for a one-off calculation you'll only need once. For a distributed team doing this repeatedly, week after week, Atlas removes the maintenance and the manual reading, for a one-time $4.99, so the overlap stays correct without anyone having to reopen and reread a grid, update a DST flag by hand, or chase down whoever owns the master copy of the file whenever a new teammate joins.
Frequently asked
What is the time-zone spreadsheet people talk about?
Why do people still use a manual spreadsheet for this?
What does the spreadsheet not do?
What's the automatic version of this?
How much does Atlas cost?
Can I still use the Vertex42 template for a one-off meeting?
Stop doing timezone math
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