πΎ Photo Storage Calculator
File sizes, card capacity, and shoot planning from your megapixels.
Shots per card
Estimates use uncompressed RAW (~2 bytes/px) and fine JPEG (~0.3 bytes/px) with 93% usable card capacity.
How to Use This Calculator
Running out of card space mid-shoot is one of the most avoidable failures in photography, and it always happens at the worst moment. This calculator turns your camera\'s megapixels into concrete numbers: how big each file is, how many shots fit on your cards, how many cards a shooting day needs, and how much total storage a multi-day trip will generate. Enter your megapixels, format, card size, daily shot count, and trip length, and plan once instead of worrying all day.
Enter your camera\'s megapixels and pick your shoot format: RAW, JPEG, or RAW+JPEG. Use the format you actually shoot, not the one you wish you shot.
Select your memory card size and enter a realistic shots-per-day number. Wedding photographers often shoot 1,500 to 3,000; a landscape trip might be 100 to 300.
Enter the trip or shoot length in days. Read the shots-per-card figure, the cards needed per day, and the total cards for the whole trip.
Add a 50 percent buffer to the card count and split the shoot across at least two physical cards. Pack the spares before you leave.
The Storage Math, in Plain English
File size scales linearly with megapixels because each pixel must be stored. A RAW file records the sensor\'s full data, roughly 12 to 14 bits per pixel plus metadata, which works out near 2 bytes per pixel uncompressed. A JPEG throws away most of that through compression, landing near 0.3 bytes per pixel at high quality settings. That 6-to-1 ratio is why switching a 45 MP camera from RAW to JPEG changes a 64 GB card from holding about 700 shots to holding about 4,700.
The 93 percent usable factor accounts for the decimal-versus-binary gigabyte gap plus formatting overhead. Manufacturers advertise 64,000,000,000 bytes as 64 GB, but your camera sees about 59.6 GiB of it, and the file allocation table takes a slice more. Planning with the full advertised number is how photographers discover mid-ceremony that the card is full 7 percent sooner than expected.
Worked Example
A 24 MP camera shooting RAW on 64 GB cards, 800 shots per day, 3-day trip. Each RAW file is about 24 x 2 = 48 MB. Usable card space is 64 x 1,000,000,000 x 0.93 = about 59,520 MB. Shots per card = 59,520 / 48 = 1,240 shots. Cards per day = ceil(800 / 1,240) = 1 card, and the 3-day trip needs ceil(2,400 / 1,240) = 2 cards, or 3 with a sensible buffer.
Switch to RAW+JPEG and each shutter press costs 48 + 7.2 = 55.2 MB, dropping the card to 1,078 shots. Switch the camera to a 45 MP body and RAW files jump to 90 MB, so the same card holds only 661 shots and the 3-day trip needs 4 cards before the buffer. This is why high-resolution shooters buy cards in 128 GB and 256 GB sizes.
Practical Tips
Buy cards from reputable brands and reputable sellers; counterfeit cards are rampant on marketplaces and fail exactly when they are full. Look for V30 or faster video speed class ratings even for stills, because fast cards clear the buffer quicker and shorten the wait between bursts. For irreplaceable shoots, use cameras with dual card slots in backup mode so every frame writes to two cards at once.
Build a download ritual for multi-day trips: each evening, copy cards to a laptop and to a portable SSD, verify the copy opened correctly, and only then format the cards in-camera for the next day. Two copies in two physical locations is the minimum that counts as a backup. Cloud upload from hotels is a nice third copy when the Wi-Fi cooperates, but never rely on it as the only backup.
Frequently Asked Questions
How big is a RAW file?
Roughly twice the megapixel count in megabytes for uncompressed RAW: a 24 MP camera produces files around 45 to 50 MB, and a 45 MP camera lands near 85 to 95 MB. Losslessly compressed RAW, which most cameras offer, cuts that by about 30 to 40 percent. The calculator uses the uncompressed estimate so your card plan has a safety margin built in.
How big is a JPEG file?
A full-resolution, high-quality JPEG is about 0.3 bytes per pixel, so a 24 MP camera makes roughly 7 MB JPEGs and a 45 MP camera makes roughly 13 MB ones. Lower quality settings or busy scenes change this, since JPEG size depends on image detail: a flat blue sky compresses far smaller than a forest full of leaves. The calculator assumes fine-quality JPEGs.
Why does my 64 GB card hold less than advertised?
Two reasons. First, card makers use decimal gigabytes (1 GB = 1,000,000,000 bytes) while cameras and computers count in binary, so a 64 GB card really holds about 59.6 GiB. Second, formatting reserves space for the file system. The calculator applies a 93 percent usable factor, which matches real-world formatted capacity closely.
Should I shoot RAW+JPEG?
RAW+JPEG gives you instantly shareable files plus full editing latitude, but it roughly doubles your storage needs and slows burst shooting on some cameras. It makes sense for weddings and client work where quick previews matter. For personal shooting, RAW alone plus fast batch exports usually serves better. The calculator has a RAW+JPEG mode so you can see the true cost.
How many memory cards should I carry?
Plan for your expected shot count plus a 50 percent buffer, then split it across at least two cards so a single card failure cannot wipe the whole shoot. For paid work, many photographers follow the rule of one card per major segment of the day (prep, ceremony, portraits, reception) so a loss is contained. Never fill a card to 100 percent; cameras can corrupt the file table on a completely full card.
Is it safe to delete photos in-camera to free space?
Avoid it when you can. In-camera deletion fragments the card and increases the chance of file-system errors, and it is easy to delete the wrong image on a small screen. Carry a spare card instead: cards are cheap, reshoots are not. Format cards in the camera you will shoot with, never on a computer, before every important shoot.