A photographer arrives at a wedding with two memory cards and confidence. By the golden-hour portraits, the camera flashes a warning: card full. The culprit is almost always the same — RAW files. A single RAW photo from a 24-megapixel camera can weigh close to 50 MB, roughly six times the size of the JPEG the same camera would produce. Shoot 2,000 frames at a wedding and you are carrying over 90 GB of data before you take a single backup. This guide explains exactly how RAW file sizes are set, how many shots fit on common cards, and how to plan a shoot so storage never becomes the emergency.
Why RAW Files Are So Much Bigger Than JPEGs
A JPEG is a finished product. The moment you press the shutter, the camera's processor decides the white balance, sharpens the edges, squeezes the colours into 8 bits per channel, and discards most of the sensor data to produce a small, shareable file. A RAW file skips all of that. It records nearly everything the sensor captured — 12 to 14 bits of brightness per channel, unsharpened and uncompressed by creative decisions — so you can fix exposure, recover shadows, and correct white balance later without the image falling apart.
That freedom is precisely why RAW files are huge. The tool's reference point makes it concrete: a 24-megapixel camera produces a JPEG of around 8 MB and a RAW file of nearly 50 MB from the very same shot. The sensor didn't change; the amount of data kept did. A card that comfortably holds 8,000 JPEGs may hold only about 1,300 RAW files.
How RAW File Size Is Calculated
RAW size is not random — it follows a simple rule tied to your camera's resolution and the RAW format you choose. Camera makers offer three broad flavours: uncompressed RAW (every bit kept), lossless compressed RAW (every bit kept, packed more efficiently), and compressed or "lossy" RAW (slightly rounded data, smallest files).
File size (MB) ≈ megapixels × rate — where the rate is 2.0 for uncompressed RAW, 1.25 for lossless compressed RAW, and 0.85 for compressed (lossy) RAW. If you also record a JPEG copy of each shot, add roughly 0.35 × megapixels per photo.
So a 24-megapixel camera shooting uncompressed RAW produces files of about 24 × 2.0 = 48 MB each. Switch to lossless compressed and the same shots shrink to about 30 MB — identical image quality, nearly 40 percent less storage. That one menu setting is the single biggest lever a photographer has.
RAW File Sizes by Camera Resolution
Using the rates above, here is what a single photo costs at popular resolutions:
| Camera resolution | Uncompressed RAW | Lossless compressed | Compressed (lossy) |
|---|---|---|---|
| 20 MP | 40 MB | 25 MB | 17 MB |
| 24 MP | 48 MB | 30 MB | 20 MB |
| 33 MP | 66 MB | 41 MB | 28 MB |
| 45 MP | 90 MB | 56 MB | 38 MB |
| 61 MP | 122 MB | 76 MB | 52 MB |
Notice how quickly high-resolution bodies escalate. A 61-megapixel camera in uncompressed RAW generates over 120 MB per shutter press — a 10-frame burst is more than a gigabyte. For sports and wildlife shooters who fire bursts of 20 frames, the RAW format choice matters more than the card brand.
How Many RAW Shots Fit on Common Memory Cards
Card capacity is straightforward once you know the per-photo size: shots ≈ (card size in GB × 1,024) ÷ file size in MB. The table below uses 24-megapixel files:
| Card size | Uncompressed RAW (48 MB) | Lossless compressed (30 MB) |
|---|---|---|
| 32 GB | ~680 shots | ~1,090 shots |
| 64 GB | ~1,365 shots | ~2,185 shots |
| 128 GB | ~2,730 shots | ~4,365 shots |
| 256 GB | ~5,460 shots | ~8,730 shots |
Two caveats. First, cards are sold in decimal gigabytes while cameras write binary megabytes, and formatting overhead eats a few percent — treat the card as roughly 93 percent of its label in practice. Second, video clips, if you record any, share the same card and devour space far faster than stills. Budget a safety margin of at least 20 percent on any paid shoot.
RAW + JPEG: What Dual-Format Shooting Really Costs
Many cameras can record a RAW and a JPEG of every shot simultaneously — handy when clients want quick previews the same evening. The price is the JPEG copy: about 0.35 MB per megapixel per shot, or roughly 8 MB extra on a 24-megapixel body. Over a 2,000-shot wedding, that adds about 17 GB on top of the RAW files.
Whether it is worth it depends on the job. For weddings and events where same-day social posts or a quick client gallery matter, dual-format pays for itself in time saved. For landscape or studio work where every file goes through careful editing anyway, the JPEGs are dead weight — shoot RAW only and keep the card space. Either way, make the decision before the shoot, not when the card fills.
Planning a Real Shoot: The Wedding Example
Consider a wedding photographer with a 45-megapixel camera shooting lossless compressed RAW, expecting 2,500 shots across getting-ready, ceremony, portraits, and reception.
- Per-photo size: 45 × 1.25 = 56.25 MB
- Total: 2,500 × 56.25 MB = 140,625 MB ≈ 137 GB
- With a 20 percent safety margin: about 165 GB needed
The plan writes itself: two 128 GB cards (one in each slot for instant backup, if the camera supports it) plus a spare 64 GB card in the bag for the dance floor. Had the same photographer shot uncompressed RAW, the total would be 220 GB — nearly double. The camera's RAW compression menu, set the night before, is worth more than any card upgrade.
The 3-2-1 Backup Rule for Photo Shoots
Memory cards fail, get lost, and get left in hotel rooms. Professional photographers follow the 3-2-1 rule: three copies of the shoot, on two different media types, with one copy off-site or at least off the camera bag.
- Copy one: stays on the memory cards until delivery — cards are cheap, reshoots are not.
- Copy two: ingested to a laptop or portable SSD at the venue or hotel the same night.
- Copy three: uploaded to cloud storage or a second drive kept separately from the main bag.
Start the first backup before you sleep, not the next morning. Card corruption almost always reveals itself at import — discovering it at home, hours from the venue, is how jobs are lost.
Tips to Stretch Card Space Without Losing Quality
- Use lossless compressed RAW as the default — identical quality to uncompressed at roughly 60 percent of the size.
- Cull in camera between segments: delete obvious misses (test shots, blinks, misfires) during downtime.
- Carry more smaller cards rather than one giant card — a failed 512 GB card loses everything; a failed 128 GB card loses a quarter of the day.
- Format in camera, not on a computer — it keeps the file system clean and avoids allocation errors that waste space.
- Budget video separately — even a few 4K clips can consume tens of gigabytes; give video its own card.
Try it now: RAW Photo Shoot Storage Calculator — enter your camera's megapixels, RAW format, and expected shots to see exactly how much card space your shoot needs, and whether it fits.
Frequently Asked Questions
How big is a RAW file from a 24MP camera?
About 48 MB uncompressed, 30 MB lossless compressed, or 20 MB compressed (lossy) RAW. Adding a JPEG copy adds roughly 8 MB more per shot.
How many RAW photos fit on a 64GB card?
At 24 megapixels: roughly 1,365 uncompressed or 2,185 lossless compressed RAW files. In practice, allow a 20 percent safety margin, so plan for about 1,100–1,750 shots.
Should I shoot RAW + JPEG or RAW only?
Shoot both when clients need fast previews or same-day delivery — it costs about 0.35 MB per megapixel extra per shot. For work that all goes through careful editing, RAW only keeps cards lighter and the workflow simpler.