Photo Compression Savings Calculator
Work out what compressing your whole camera roll would actually free. Set your photo count, current format and target quality, and see the library size before and after, the GB and percent saved, the cloud tier it drops you to, and how that compares with just deleting the junk.
Photo Compression Savings Calculator
Your library
Photos app, Library tab, bottom of the grid. Photos only: leave videos out and use the video storage calculator for those.
3.5 MB is a realistic mixed roll, because screenshots and older shots pull the average below a pure 12 MP JPEG. Changing the format below refills this with that format's typical 12 MP size.
JPEG is the Most Compatible setting on iPhone and the default on most Android cameras.
Compress to
No visible change. You are only swapping the codec, not throwing away detail.
File size tracks pixel count, so the factor is the scale squared: 75% leaves 56% of the bytes, half leaves 25%.
Cloud storage
US pricing. iCloud+ starts at 50 GB, Google One at 100 GB.
Compression is scene-dependent: a flat sky squashes far harder than foliage, so read every figure as give or take 20%.
What it does to the bill
The tier is matched against your photo library alone. Backups, mail, messages and files sit in the same plan, so compressing may not actually drop your tier. Price the whole thing with the iCloud storage cost calculator.
Or delete instead
That is 22% of the library, the duplicate and blurry share our cleanup estimator uses, and it costs no quality at all. The duplicate photo space calculator breaks out the duplicate half on its own.
Clean up your camera roll with Swipe44
Compressing a keeper buys back half its size. Deleting a duplicate buys back all of it. Swipe44 groups duplicates on your phone, lets you swipe right to keep and left to delete, then wipes the whole marked pile behind one system confirmation and tells you how much space came back.
What the numbers assume
- Format factors come from the fleet per-megapixel constants used by the photo file size calculator: HEIC 0.21, JPEG 0.42, PNG 1.0, RAW 1.1, ProRAW 2.1 MB per megapixel. JPEG to HEIC is 0.21 / 0.42, so half.
- Quality factors assume your source is a camera original at roughly q90 to q95. A photo that has already been through a messaging app, a re-upload or a screenshot will save less than this and lose more quality, because each re-encode re-quantises the previous encoder's noise.
- The quality curve is measured on JPEG encoders. Applying it to a HEIC re-encode is an approximation, on the assumption that both are DCT-style lossy codecs with a similar quality to size response.
- Resizing is applied as the square of the scale, because compressed size tracks pixel count at a fixed format and quality. Options are relative, since the calculator never asks for your source megapixels.
- Gigabytes are decimal (1 GB = 1,000 MB), matching every other Swipe44 tool and the way storage plans are sold.
What actually shrinks a photo library
There are three levers, in order of effect. The codec is the big one: HEIC holds about the same picture in half the bytes of a JPEG, which is Apple's "up to 2X" figure for HEVC and the reason High Efficiency has been the iPhone default since iOS 11. The quality setting is next, worth roughly 30% to 40% at q85 measured against a decent original. Pixel count is third, and it is the most brutal: file size tracks pixels, so halving both dimensions leaves about a quarter of the bytes.
The levers multiply rather than add. JPEG to HEIC at q85 with a half-size resize is 0.50 x 0.65 x 0.25, which is 8% of the original library. That looks implausible until you do the arithmetic, and it is also a good illustration of why the aggressive settings are not free.
Two caveats sit on every number here. How well a photo squashes depends on what is in it, and a flat sky gives up far more than a field of foliage, so treat each figure as give or take 20%. And RAW or ProRAW sources produce enormous headline savings (ProRAW to HEIC is a 90% cut) precisely because they hold editing headroom that a lossy target throws away permanently.
The quality you trade for the gigabytes
A straight codec swap at the same quality costs you nothing visible. You are re-containering the picture, not discarding detail. Quality 95 is close behind: visually lossless for normal viewing, and it barely saves anything, because the camera already compressed the file once. Quality 85 is the honest middle, hard to spot on a phone screen, with fine gradients and skies the first place it shows. Quality 70 is where it becomes visible on close inspection: soft edges and blocky patches in sky and shadow.
Quality 100 is a wasted setting: it stores the encoder's full precision for gains no eye can see. That is also why the popular claim that dropping to 85 saves 50% to 60% is misleading here. It measures against a quality-100 master, and no phone ever writes one. Against a camera original at roughly q90 to q95, the measured band is 30% to 40%, and that conservative figure is what this calculator ships.
One more thing the estimates assume: camera originals. A photo that has already been through a messaging app, a re-upload or a screenshot has been re-encoded once, and every re-encode re-quantises the previous encoder's artefacts as though they were real detail. Those files shrink less and degrade more. And all of it is irreversible: once the original is overwritten there is no undo, so keep an untouched copy of anything you would print or crop hard.
Compress or delete? Run both numbers
Compressing a keeper halves it at best. Deleting a duplicate frees all of it, and nothing you keep gets worse in the process. On a typical camera roll about 16% of photos are near-duplicates and another 6% are blurry throwaways, which is the 22% the calculator shows as the delete-instead figure. Add burst frames and screenshots of things you dealt with months ago and the recoverable share climbs further.
Compare the two figures above before you re-encode anything. For a library that is already HEIC, deleting is the only lever left that does not cost quality. For a JPEG library the codec swap is genuinely worth doing, and it stacks with a cleanup rather than competing with it.
That cleanup is what Swipe44 is for. You work the roll by swiping, right to keep and left to delete, through Recents, Random, or one month at a time. Duplicates are hashed on-device and grouped for review. Everything you mark collects in a pending pile, then the whole batch goes at once behind a single system confirmation, with the freed space reported and tallied. Nothing is uploaded, and iCloud originals are never downloaded. For the full delete-side numbers, the camera roll cleanup estimator and the duplicate photo space calculator break it down properly.
What this does not cover
Videos are excluded. They compress on completely different rules and they usually dwarf the photo library, so put them through the video storage calculator instead. Single-photo sizing is not here either: if the question is how many MB a 12 MP HEIC weighs, the photo file size calculator answers it per shot and per format.
The cloud readout counts photos only. Device backups, mail, messages and files draw on the same plan, so a library that drops below a tier ceiling on this page may still not move your bill. Run the whole allowance through the iCloud storage cost calculator before you count on a downgrade.
Frequently Asked Questions
Common questions about photo compression savings calculator
How much space does compressing photos actually save?
Converting a JPEG library to HEIC roughly halves it: 8,000 photos at 3.5 MB is 28 GB, and the same shots as HEIC land near 14 GB. Apple's own figure for HEVC is "up to 2X" the compression of JPEG at the same quality, which is why iPhones have shot HEIC by default since iOS 11. If your photos are already HEIC, that saving is already banked and re-converting frees nothing, so the only levers left are dropping quality, resizing, or deleting. The per-photo side of this is covered in the photo file size calculator.
Does compressing photos lose quality?
Yes, if the compression is lossy, and it is irreversible. A JPEG or HEIC re-encode discards image data permanently, and there is no undo once the original is gone. A format swap at the same quality setting (JPEG to HEIC) is close to invisible. Dropping to quality 85 is hard to see on a phone screen. Quality 70 shows up as soft edges and blocky patches in skies and shadows. Keep an original of anything you would print or crop hard.
Is it better to compress photos or delete them?
Deleting usually wins, and it wins without any quality cost. Compressing a keeper halves it at best, while deleting a duplicate frees all of it. On a typical camera roll about 16% of photos are near-duplicates and another 6% are blurry throwaways, so roughly a fifth of the library can go without anyone missing it. The camera roll cleanup estimator runs that number properly. Swipe44 works that pile first: swipe left on what you do not want, and the whole batch is deleted with one system confirmation.
Should I turn on High Efficiency on my iPhone?
If you want smaller photos going forward, yes. Settings, then Camera, then Formats, then High Efficiency, which is HEIF and HEVC. Apple's other option, Most Compatible, writes JPEG and H.264 for maximum compatibility with older software. Apple's own guidance is that HEIF and HEVC "use less storage space on your devices and iCloud Photos, while preserving the same visual quality." Note that this only changes new shots. It does not convert the photos already on your phone.
Does compressing a photo that is already compressed save the same amount?
No, and it costs more quality than the figures here suggest. Every pixel-level re-encode re-quantises the previous encoder's artefacts, treating compression noise as real image detail (the photocopier effect, known as generation loss). A photo that has already been through a messaging app or a re-upload will shrink less and degrade more. The estimates on this page assume you are starting from camera originals.
Does iCloud compress my photos automatically?
Not the originals. iCloud Photos keeps your photos and videos in their original, high-resolution version in iCloud. What Optimize iPhone Storage does is keep smaller versions on the device while the full-size file stays in the cloud. That frees space on the phone but not in your iCloud allowance, which is why an Optimize Storage user can still hit the 5 GB free tier. Actually compressing the library is the only thing that shrinks the iCloud side, and the iCloud storage cost calculator prices what is left.
Does resizing save more than compressing?
Often, yes. File size tracks pixel count, so halving both the width and the height removes three quarters of the pixels before the encoder makes a single quality decision. Cutting a 12 MP photo to half dimensions leaves roughly a quarter of the bytes. The catch is that it is permanent and it kills your ability to crop or print, so it is a reasonable move for screenshots and receipts and a bad one for photos of people.
What about WebP and AVIF, are they smaller than HEIC?
They are web formats, not camera-roll formats, so no phone will shoot them and your Photos app will not thank you for them. For reference: Google's own study puts WebP at 25% to 34% smaller than JPEG at equivalent quality, and MDN reports AVIF at a median 50% saving against the same JPEG set, roughly where HEIC already sits. On a phone library HEIC is the format that matters, because it is the one the camera and the Photos app both handle natively.