Choosing the Right SD Card for the Nikon D7100

The Nikon D7100 doesn’t come with a memory card in the box. Unless you picked up a retailer bundle, you’ll need to grab one before you can start shooting.

If you look at the camera’s original instruction manual, the “Approved Cards” list is hopelessly outdated. The camera was released back in 2013, and memory card technology has lapped it several times over. If you aren’t careful, it’s incredibly easy to walk into a store today and spend a fortune on a high-speed card that this camera simply cannot use.

Here is a practical breakdown of exactly what the D7100 requires, the hardware limits you need to know about, and some cost-effective recommendations.

Compatibility & requirements

To cut through the confusing marketing jargon printed on memory card packaging, here are the hard technical limits of the Nikon D7100:

• Physical Size: Standard SD cards. (You can technically use a microSD card if you put it inside an adapter sleeve, but I’d advise against it. The adapter adds another physical connection point that can fail or slow down data transfers).
• Format Compatibility: It supports SDHC (cards up to 32GB) and SDXC (cards 64GB and larger).
• Bus Interface Limit: The camera’s internal card reader is limited to UHS-I speeds.

That last point about the UHS-I interface is the most important piece of information for your wallet.

The money-saving rule: Don’t overpay for speed

If you walk into a camera store today, the salesperson will likely point you toward blazing-fast UHS-II cards with a V90 speed rating. For modern mirrorless cameras shooting 8K video, those cards are essential. But for the D7100, they are a waste of money.

UHS-II cards achieve their incredible speeds by using a second row of physical connection pins on the back of the card. The D7100 was built before that second row was invented. If you put a $150 UHS-II card into this camera, it will safely “downshift” and work just fine, but it will only use the first row of pins. It will perform exactly like a $20 UHS-I card inside the camera.

The only place you’ll see a benefit from a UHS-II card is when you take it out of the camera and plug it into a fast computer reader to offload your files. But for actual in-camera performance — clearing the photo buffer or recording 1080p video — you can confidently skip the expensive V90 cards.

Warning: While backward compatibility generally works fine for UHS-II, you should actively avoid buying newer SD Express cards. The architecture is different enough that an SD Express card will often perform noticeably slower in an older UHS-I camera than a standard, cheap SD card.

Practical SD card recommendations

Based on extensive SD card speed testing, the sweet spot for the Nikon D7100 is a highly-rated UHS-I card with a V30 (or U3) speed class. This maxes out the camera’s internal hardware and guarantees a smooth video recording experience without dropping frames.

Here are a few extremely reliable, cost-effective options that are readily available:

Things worth knowing

What size memory card works best?

You can use cards from 4GB all the way up to 256GB and beyond. Because the D7100 features dual slots, I’ve always found it more practical (and often cheaper) to buy two 64GB or 128GB cards rather than one massive 256GB card.

Here is an estimate of how many photos or minutes of video you can expect to fit on a card, based on Nikon’s official data for the standard DX crop mode. Keep in mind that compressed formats vary slightly in size from file to file depending on the visual complexity of the scene.

Quality Setting	Size Setting	File Size MB (approx)	16GB	32GB	64GB	128GB	256GB	Buffer Capacity
NEF (RAW), Lossless compressed, 12-bit		22.7	191	382	764	1528	3056	7
NEF (RAW), Lossless compressed, 14-bit		28.5	148	296	592	1184	2368	6
NEF (RAW), Compressed, 12-bit		20.2	260	520	1040	2080	4160	9
NEF (RAW), Compressed, 14-bit		24.9	217	434	868	1736	3472	8
JPEG Fine	Large	12	507	1014	2028	4056	8112	33
	Medium	7.4	853	1706	3412	6824	13648	100
	Small	3.8	1600	3200	6400	12800	25600	100
JPEG Normal	Large	6.2	1000	2000	4000	8000	16000	100
	Medium	3.7	1600	3200	6400	12800	25600	100
	Small	1.9	3200	6400	12800	25600	51200	100
JPEG Basic	Large	2.9	1900	3800	7600	15200	30400	100
	Medium	1.9	3200	6400	12800	25600	51200	100
	Small	1	6000	12000	24000	48000	96000	100

Estimates are calculated from Nikon’s estimates (p.348 in D7100 product manual). Refers to DX crop mode; files when using 1.3x crop mode are smaller.

How to use the dual card slots

The camera will work perfectly fine if you only put one card in Slot 1. You don’t have to use both. But if you do put two cards in, you can jump into the Shooting Menu and configure how the camera treats them. The cards do not have to be the same size or brand.

• Overflow: The default setting. The camera fills up Slot 1, and then automatically starts writing to Slot 2 so you don’t have to stop shooting.
• Backup: The camera writes identical copies of every photo to both cards simultaneously. If a card ever fails, you have an immediate backup.
• RAW Slot 1 / JPEG Slot 2: A great workflow option where the camera saves the heavy, editable RAW file to the first card, and a smaller, easily shareable JPEG to the second.

The golden rule of formatting

Whenever you buy a new memory card, or whenever you want to clear off an old one, you should format the card directly inside the camera, not on your computer.

Formatting the card in the camera builds the exact file and folder architecture the D7100 expects to see. If you simply drag your files to the trash on your Mac or PC, you leave behind hidden indexing files that can eventually corrupt the card and cause write errors in the middle of a shoot.

If you ever make a mistake and format a card before you meant to, stop shooting immediately. Pull the card out of the camera. As long as you don’t overwrite the data with new photos, it is usually quite easy to recover those deleted photos using simple software on your computer.