iMessage Storage Calculator
Messages is usually one of the biggest things on an iPhone, and almost none of it is text. Tell it how many photos and videos go through your chats in a normal week and how far back your history goes. You get the gigabytes of attachments sitting in Messages, the split between photos, video and the small stuff, what Keep Messages at 1 Year or 30 Days would hand back, and what those attachments cost you a year in iCloud+.
iMessage Storage Calculator
What goes through your chats
Count both directions. Group chats are where this runs away.
Video is a few percent of the items and most of the gigabytes.
Small individually, not small in aggregate.
If Keep Messages is set to Forever, this is however long you have had the phone number.
Attachment sizes
Sets the average size. Override below if you know yours.
Auto-fills from the choice above.
Apple caps a standard iMessage attachment around 100 MB.
Auto-fills from the choice above.
The second copy, and the bill
Anything you sent came from your camera roll. Anything you tapped Save on went into it.
Only used to price the attachments. Leave it if you are not sure.
Nothing to size here, put some numbers in.
At the rate you just described, with nothing deleted along the way.
What clearing it would get you
What they cost you in iCloud+
2026 US iCloud+ pricing. Messages attachments only count against iCloud once Messages in iCloud is switched on.
The copies in your camera roll are the other half
Clearing Messages only gets you the message copies. The originals you sent and the pictures you saved out of chats are still in Photos, along with the near-identical shots around them. Swipe44 is for that side: swipe right to keep, left to mark. It hashes visual duplicates on the phone and groups them for you, then deletes the whole marked batch behind one confirmation and tells you what came back.
How much Messages storage a three-year history builds up
| Profile | Photos/wk | Videos/wk | 3-year total |
|---|
At your photo and video sizes, over 36 months, including a matching amount of GIFs, voice notes and stickers.
What is actually filling up your Messages
Text is free, attachments are the bill. A text-only message is one to five kilobytes, so thousands of them come to under a megabyte. Everything you see on the iPhone Storage screen under Messages is photos, videos, GIFs, voice notes, stickers and files, kept in the Messages database until something deletes them.
| Attachment | Typical size |
|---|---|
| Text-only message | 1 to 5 KB |
| Image sent with Low Quality Image Mode on | About 100 KB |
| Sticker | Up to 500 KB |
| GIF | Around 600 KB |
| Screenshot or meme | Under 1 MB |
| Voice note, one minute | 0.4 to 1 MB |
| Camera photo, 12 MP HEIC | 2 to 3 MB |
| Camera photo, 48 MP HEIC | 2 to 5 MB |
| 1080p video, one minute | 40 to 50 MB |
| 4K clip | 100 to 200 MB |
For a rough sense of scale: 1 to 3 GB is casual messaging, 5 to 15 GB is anyone in active group chats, and a long history with video in it goes well past that. A standard iMessage attachment is capped around 100 MB, which puts a ceiling on how bad any single item can be, and no ceiling at all on the total. If your result comes out mostly video, the video storage calculator breaks down the per-minute rates by resolution and frame rate.
How to see and clear your Messages storage on iPhone
In order of return on effort:
- See the number: Settings, General, iPhone Storage, Messages. The line marked Documents & Data is your attachments.
- Review Large Attachments: on the same screen. iOS lists every attachment across every conversation sorted by file size, so it is a videos-first screen in practice. Tap Edit, select, delete.
- Auto Delete Old Conversations: the bulk sweep, also on that screen.
- Keep Messages: Settings, Apps, Messages, Keep Messages, then 30 Days, 1 Year or Forever. Changing it deletes retroactively, so save anything you want first.
- Audio Messages: Settings, Apps, Messages, Audio Messages, Expire, After 2 Minutes stops voice notes accumulating at all.
- Recently Deleted: in Messages, tap Filters or Edit, then Recently Deleted. Items sit there for up to 30 days and keep taking up space until you clear them.
That last step is the one everyone skips before deciding the deletion did not work. To see where Messages sits against everything else competing for the same gigabytes, the phone storage planner budgets the whole device.
Why deleting the message does not always free the space
Three reasons, and between them they explain most of the confusion. First, Recently Deleted holds messages and attachments for up to 30 days, so the space comes back on Apple's schedule and not yours unless you empty it. Second, iCloud: with Messages in iCloud on, the delete has to sync before your quota drops, and without it, deleting on the phone does nothing to iCloud. The iCloud storage cost calculator covers which tier you actually need once Messages is in the picture.
Third, and the one nobody mentions: the copy in your camera roll is a different file. Take the default result above. Around 25.6 GB in Messages, of which 5.7 GB is photos, and roughly 2.6 GB of those photos exists a second time in Photos. Delete the conversation and that 2.6 GB stays exactly where it is.
The camera-roll half of the problem
Clearing Messages gets you the message copies and nothing else. The originals you sent, the pictures you tapped Save on and the near-identical bursts around them are still in the camera roll, along with everything that never went near a chat. That pile is what Swipe44 is for. You go through it one photo at a time, swipe right to keep and left to mark, working from Recents, Random or a single month so it stays a few minutes rather than an afternoon. Visual duplicates get hashed on the phone and grouped so you can compare them side by side. Everything you marked goes in one batch behind a single system confirmation, and you get told how much space came back. Nothing is uploaded. iCloud originals are never downloaded.
To size that side before you start, the duplicate photo space calculator estimates how much of your library is copies of things you already have.
Frequently Asked Questions
Common questions about imessage storage calculator
Why does Messages take up so much storage on my iPhone?
Because it keeps everything, and by default it keeps it forever. Text is nothing: thousands of text-only messages come to under 1 MB, since each one is a few kilobytes. The gigabytes are attachments. Photos, videos, GIFs, voice notes, stickers, files, all sitting in the Messages database indefinitely unless you tell iOS otherwise. Casual messaging usually lands around 1 to 3 GB. Anyone in active group chats is more like 5 to 15 GB, and a long history with a lot of video in it goes well past that.
How much space does one iMessage photo or video actually use?
A full-quality camera photo sent over iMessage is roughly the same as the original: about 2 to 3 MB for a 12 MP HEIC, and 2 to 5 MB for a 48 MP one. Screenshots and memes are smaller, usually well under 1 MB. Turn on Low Quality Image Mode and every image you send is recompressed to around 100 KB regardless of what it started as. Video is the expensive part: a minute of 1080p sent through Messages measures about 40 to 50 MB, and a single 4K clip typically lands at 100 to 200 MB. The video storage calculator covers the per-minute rates in more detail.
What does "Documents & Data" mean under Messages?
Go to Settings, General, iPhone Storage and tap Messages. The app itself is a fixed few hundred megabytes. "Documents & Data" is everything it has piled up since day one: your conversation database plus every attachment ever sent or received. When that number reads 8 GB, essentially all 8 GB is attachments. You cannot delete and reinstall Messages to clear it, which is why the storage screen offers Review Large Attachments and Auto Delete Old Conversations instead.
How do I delete large iMessage attachments?
Settings, General, iPhone Storage, Messages, Review Large Attachments. iOS lists every attachment across all your conversations sorted by file size, biggest first, so the videos come up top. Tap Edit, select the ones you do not want, and delete. It is the fastest way to get gigabytes back, because a handful of videos usually accounts for most of the total. You can also delete one item inside a chat: touch and hold the bubble or attachment, tap More, then delete.
Does deleting a conversation free up storage right away?
Not immediately. Deleted messages and attachments go to a Recently Deleted folder and stay there for up to 30 days so you can recover them, and they still occupy space that whole time. To get the room back now, open Messages, tap Filters or Edit at the top of the conversation list, choose Recently Deleted, select what is in there and delete it permanently.
Should I set Keep Messages to 30 Days or 1 Year?
Settings, Apps, Messages, Keep Messages gives you 30 Days, 1 Year and Forever, and it deletes messages plus their attachments once they pass that age. Forever is the default, which is why people end up with 20 GB of Messages. One year is the middle setting most people want: it clears the deep backlog and keeps anything from the last twelve months. Thirty days is aggressive. Good for a phone that is genuinely out of space, painful the first time you go looking for an old photo someone sent you. Switching the setting deletes retroactively, so back up anything you care about first.
Does turning on Messages in iCloud free up iPhone storage?
Partly. Mostly it moves the problem rather than solving it. With Messages in iCloud on, your conversations and attachments sync up and iOS can offload the larger attachments from the device when it is short on room. But those attachments now count against your iCloud quota, so a 20 GB Messages history eats 20 GB of your plan. The upside: with it on, deleting a message or attachment on one device removes it everywhere, iCloud included. With it off, deleting on the phone does nothing to your iCloud copy. The iCloud storage cost calculator prices what that quota is worth.
Do message attachments duplicate photos I already have?
Often, yes, and in both directions. Every photo you send came out of your camera roll, and Messages then kept its own separate copy, so that picture is now stored twice on the same phone. Every photo you tapped Save on went the other way, into your camera roll, while the copy in the conversation stays exactly where it was. Deleting one never removes the other. So clearing Messages and then finding your camera roll still full is not a contradiction. They are two piles of the same pictures, and both need a pass. The duplicate photo space calculator sizes the camera-roll side.