Almost everyone overestimates this. A photo at an iPhone's default settings is about 3.5 MB, so a whole wedding's worth of guest photos is smaller than the video of one speech. If you know those two figures you can size any event on the back of an envelope, and you will usually find the answer is "less than you thought, until video shows up."
The rule of thumb
Two numbers do all the work here, both from an iPhone at its default camera settings, which is what most guests carry and few of them ever change:
- A photo (24 MP, the default): about 3.5 MB.
- A minute of video (1080p at 30 fps, the default): about 65 MB.
That ratio is the whole story. One minute of video weighs nearly what twenty photos weigh. Everything below is those two numbers with different guest counts poured into them.
Your plan is a total stored size, not an item count, which is why the math works this simply. A thousand small photos and one long video come out of the same pool. The help center has the mechanics: storage, plans and limits.
What an event produces
Three sketches, from events you would expect to look very different:
A wedding with sixty guests. Not everyone uploads, and the ones who do upload in bursts: getting ready, the ceremony from the aisle seat, the first dance from four angles, the sparkler exit. Call it a few hundred photos in total, plus whatever the couple adds themselves afterwards. In bytes that is small. A wedding only gets big when guests start filming the toasts, because a handful of speeches can outweigh every photo taken all day. Setting one up from scratch? Start at the wedding photo QR guide.
A kid's birthday party. An afternoon, a dozen parents, most of them shooting bursts of the same cake moment. Roughly a hundred photos and a few short videos of the candles. This is the smallest realistic event, and it fits in any paid plan many times over.
A two-day conference. More people, but a much lower rate per person: badge photos, the keynote stage, the booth, the dinner. Sessions produce fewer pictures than parties do, because people are sitting still and listening. The volume comes from the length of the program, not the size of the room, and sizing a whole program of events is its own question: corporate event photo sharing.
Which plan holds it
Every figure in this table is at an iPhone's default camera settings.
Read those "roughly holds" figures as the photo-only ceiling and then subtract for video at the ratio above. Against the three sketches, the free tier is a taste rather than a plan: it runs the whole flow on a small gathering, and the birthday party's hundred photos already outgrow it. It holds 1 event and takes photos only, which is why most weddings, and most parties with a cake worth filming, end up on an Event Pass: one event, one payment, video included. The full grid is on the pricing page.
When video changes the math
Video is the only thing that turns a comfortable event into a tight one, and it does it fast. A single guest who films the entire first dance uses more space than the twenty people photographing it.
So plan for video first and photos second. If you know there will be speeches, toasts, a performance, or a group of teenagers who film everything, size up. If your event is a photo event with the occasional short video, the estimates above hold and you have room to spare.
Two practical consequences. First, video only exists on paid plans at all, so a free event never has this problem: it collects photos and stops. Second, per-file size is a separate ceiling from your plan's total, and it is generous: any single upload can be up to 10 GB, on every plan, which is large enough that no one at your event will hit it by accident.
What happens as you fill up
You will not be surprised by it. The dashboard carries a meter that counts what is stored right now, with what waits in Deleted drawn beside the albums, since a deleted photo still counts until it leaves. Emptying Deleted gives the space back at once, and with Make room from Deleted on, a new upload takes its room from the oldest of it without anyone lifting a finger.
If an event does outgrow its plan, moving up is the fix and it does not disturb the album: same link, same photos, more room. What never happens is a silent cull. That is a whole subject of its own, covered in why your album has no expiry date.
Size your event with the two numbers at the top, then pick the row that clears it with headroom on the pricing page.
