Short answer: photos are almost never one thing. That block in the storage screen is the library, Recently Deleted, copies that other apps keep, and cache — and on most phones the library is the only part worth acting on. Two things are worth knowing before you delete anything: iCloud's Optimize iPhone Storage frees local space only after the upload finishes, and photos you delete stay recoverable (and still count against your storage) for 30 days. This page is about the inside of the photo block itself; if your whole phone is below 10% free, start with Why Storage Space Affects Speed instead.
First: confirm what photos actually take
Open Settings → General → iPhone Storage. The coloured bar is a proportional chart, not a ranking, so read the list below it for numbers. Tap Photos and you get a breakdown of the library itself; the app list entry shows how much the Photos app holds in total.
Read it in this order:
- The Photos row in the app list — the honest number for everything the Photos app stores, including its thumbnails and database.
- The bar versus the list. They do not always add up. A category can look small in the bar and still be several GB. Trust the list, and treat the bar as a shape.
- The colour. Photos has its own colour; if two colour segments look similar, tap each one. System Data is a reporting bucket rather than a folder, which is why it never matches anything you can see — see What Is System Data.
- The free-space figure at the top. Compare it against the headroom your model should keep in How Much Free Space to Keep; "a few GB left" is not the same as enough.
If Photos is the top row by a wide margin, the rest of this page applies. If something else is on top, deal with that first and come back.
What is inside the photo block
| Part | Typical size | Safe to clear? | What it costs you |
|---|---|---|---|
| Library originals (camera photos and videos) | The bulk: tens of GB on a used phone; video dominates | Only with a confirmed copy elsewhere | Deleting without a copy is permanent. Export to a computer, or turn on iCloud Photos and let the upload finish first |
| Recently Deleted | Often a few GB; tens of GB if you deleted a lot lately | Yes, deliberately | Permanent once emptied. Open the album first and recover anything you want back |
| Live Photos | Each adds roughly a two-to-three second video clip | Yes, per item: keep the still, drop the motion | The motion effect is gone, and it does not come back from iCloud either |
| Videos already optimised or trimmed | Individual clips of 200MB to several GB | Yes, if you have watched and no longer need them | Re-downloading costs data and time; anything rented or streamed again may no longer be available |
| Shared albums | Small locally — items stay in iCloud | Removing the album only unsubscribes | You stop seeing the album; the owner's copy is untouched, and nothing of yours is freed |
| Hidden album | Counts like any other album | Not a space category at all | Hiding an item changes visibility, not storage. Deleting from Hidden deletes the photo for real |
| Images received in Messages | Often 1-10GB, counted under Messages | Yes, in batches inside the app | Attachments are gone permanently. Keep the ones you still need |
| Photos app cache and thumbnails | Usually under 1GB, occasionally a few | No direct control | iOS rebuilds it. Reinstalling the app is the only reset and it is rarely worth it |
Two entries in that table are the most misread. Shared albums feel like they should cost space because they sync, but shared items are held in iCloud and count against your iCloud storage, not your device. Recently Deleted is the opposite: those items are still on the phone, still consuming local space, for 30 days after you delete them.
Optimize iPhone Storage versus Download and Keep Originals
iCloud Photos has a single switch with two settings, and the difference is entirely about what stays on the device:
- Optimize iPhone Storage keeps a device-sized version locally — smaller previews for older items — and downloads the full-resolution original when you open, edit or share it. Your iCloud library stays complete.
- Download and Keep Originals keeps every full-resolution file on the phone as well as in iCloud. Choose this only if you want the phone itself to hold everything, for example before travelling without reliable data.
Two honest caveats. First, optimisation is not instant and not total. iOS decides what to evict based on how much space it needs and how recently you used an item, and it will not evict much on a phone with plenty of free space. On a nearly full device you will see a real change within days; on a half-empty one you may see almost nothing. It also tends to free less than people expect, because recent photos and video are kept locally.
Second, and this is the part that causes data loss: never delete local copies while the upload is still running. iCloud Photos uploads in the background, and a large library can take days on a slow connection. Deleting the library, or restoring the phone, before that finishes removes the last copy of anything not yet uploaded. Before you clear anything, open Photos, scroll to the bottom of the Library tab, and look for a sync status or a pending-items count. If it is still working, stop and wait.
The same rule applies to the "delete everything and re-enable iCloud Photos" trick that circulates online. It works only for someone whose full library is already in iCloud.
"I deleted photos but the space did not change"
Three explanations cover most cases:
- Recently Deleted has not been emptied. Deleted photos move to
Photos → Albums → Recently Deletedand keep their space for 30 days before iOS removes them automatically. Empty it deliberately, after checking the album once. - A move is still in progress. A large delete, restore from backup or iCloud upload means the number is mid-flight. Screenshots of the storage screen taken minutes apart can genuinely differ. Check once a day instead of once an hour.
- The space belongs to a copy another app holds. Photos you received in Messages, saved to Files, exported into an editing app, or attached to a note exist in those apps too. Deleting the item in Photos leaves those copies untouched, and they show up under the other app. Attachments in Messages are the usual culprit.
A fourth case, less common but real: the storage screen itself recalculates lazily. Give it a moment and a restart before concluding that nothing happened.
Order to work in
Cheapest and safest first, and stop when you have enough room:
- Check for a pending iCloud upload. Never skip this while iCloud Photos is on. It costs nothing and it is the one step that prevents permanent loss.
- Empty Recently Deleted. Two taps, space you already decided to give up, usually a few GB. Open it first.
- Clear the biggest attachments inside Messages and other apps that keep their own copies.
- Review videos. They are the least efficient use of local space: a few long 4K clips can outweigh thousands of photos. Export the ones you care about, then delete.
- Trim or convert Live Photos if you want space without losing the still image.
- Turn on Optimize iPhone Storage, then leave the phone plugged in on Wi-Fi overnight and let the upload finish. This is the largest long-term win, and also the slowest to do safely.
- Export to a computer and delete locally only if iCloud is not an option, and verify the export opens before deleting anything.
Skip the third-party "storage booster" apps. iOS sandboxing means no app can reach another app's files or iCloud, so a cleaner cannot empty Recently Deleted for you or shrink the library.