Best Memory Cards for the Sony FX3 – CFexpress Type A and SD Card Guide

The Sony FX3 has two card slots, and each one takes either a CFexpress Type A card or a UHS-II SD card. It shares its 12MP sensor, BIONZ XR processor, and card slots with the Sony A7S III, and in my A7S III tests the fastest V90 SD cards wrote 235–243 MB/s while V60 cards wrote 82–138 MB/s. I recommend CFexpress Type A for this camera: it’s the only card Sony supports for XAVC S-I 4K slow motion, and it now costs about the same as a good V90 SD card.

Sony FX3 – Amazon / B&H

How I Tested

The SD card numbers come from my in-camera tests of the Sony A7S III (tested 2021), which uses the same sensor, processor, and card slots as the FX3, so the results carry over. I shot Uncompressed RAW bursts until the buffer filled and divided the data written by the time the camera took to clear it, using the fastest run for each card. With CFexpress Type A cards the A7S III buffer never filled: they wrote about 240 MB/s, which is as fast as the camera produces Uncompressed RAW at 10 fps. For card-to-card CFxA comparisons, see my Sony A7V tests, where every CFxA card hit about 310 MB/s.

Quick Picks for the Sony FX3

	Best value CFxA: Lexar SILVER CF4.0 Type A. Every CFxA card I tested in the A7V hit about 310 MB/s, so paying more doesn’t make the FX3 record any better. The SILVER is rated for 200 MB/s minimum sustained writes, above the FX3’s highest bitrate (1200 Mbps, or 150 MB/s).
	Pro CFxA: Delkin BLACK CF4.0 Type A. Same in-camera speed as the SILVER, since the camera is the limit. Buy it if you want Delkin’s lifetime warranty.
	Best SD card: Angelbird AV PRO V90 MK2. 242 MB/s in my A7S III tests, within 1 MB/s of the fastest SD card. V90 is what Sony requires for 600 Mbps XAVC S-I on an SD card.
	H.265 on a budget: Lexar ARMOR Gold V60. Wrote 194 MB/s in the A7V, the fastest V60 card I’ve tested in-camera. V60 covers XAVC HS and XAVC S at up to 280 Mbps, but not XAVC S-I.

What about Sony cards? I like Sony’s own cards in a lot of Sony cameras because they perform so well. The Sony TOUGH G V90 was the fastest SD card in my A7S III tests at 243 MB/s. But Sony has suspended orders for nearly all of its SD and CFexpress cards because of the global flash memory shortage, so they’re hard to find right now, and Sony has had bad cards and recalls in the past. The picks above were just as fast in my tests and are easier to buy. If you find a TOUGH G at a fair price, it’s still a good card.

How the FX3’s Two Card Slots Work

Both slots take either card type, so you can run two CFxA cards, two SD cards, or one of each. Set it under Rec. Media Settings:

• Backup (Simult. recording): records movies, stills, or both to both cards at once. The two cards need the same file system: CFexpress Type A and SDXC cards both use exFAT, but an SDHC card (32GB or smaller) uses FAT32 and won’t pair with them. For backup recording, the slower card has to meet Sony’s requirement for the format you shoot.
• Relay (Auto Switch Media): switches to the second card when the first one fills, so a long take or event day keeps going.
• Sort: sends RAW to one card and JPEG or HEIF to the other, with movies going to the priority slot.

If you run one of each, put the CFxA card in the slot you record movies to and use a V90 SD card for backup.

CFexpress Type A or SD Cards for the Sony FX3?

On the Sony FX3, the codec decides. Sony requires a CFexpress Type A card (VPG200 or higher) for XAVC S-I 4K slow motion and for XAVC S-I HD at 240fps or 200fps. Everything else also works on SD cards. CFxA cards now cost about the same as good V90 SD cards, offload much faster, and the A7S III buffer never filled with one, so they’re the better buy for this camera.

CFexpress 4.0 Type A cards work in the FX3, but the camera can’t use their extra speed. Buy one if the price is right or you want faster transfers to your computer with a 4.0 reader. The Lexar SILVER is the best value; if you want more, the Sony TOUGH G and Delkin BLACK cost more for the same in-camera speed. See my CFexpress Type A benchmarks for reader speeds.

V90 vs V60 SD Cards in the Sony FX3

In the Sony A7S III, the fastest V90 cards wrote 235–243 MB/s and V60 cards wrote 82–138 MB/s. Sony requires V90 for XAVC S-I (600 Mbps in 4K, 222 Mbps in HD) on an SD card. V60 covers XAVC HS and XAVC S at up to 280 Mbps, and slow motion in those formats, though Sony says you may need V90 at 120fps or 100fps in 4K and at 240fps or 200fps in HD. If you only shoot H.265, a V60 card saves real money.

Older or smaller V90 cards can be much slower: the Lexar 2000x, Transcend, and pre-Iridium ProGrade V90 cards wrote 128–133 MB/s, slower than the best V60 cards.

Current CFexpress Type A Cards I Recommend

I update this list as new cards come out. The speeds are from my card reader tests, so they show what each card can do, not what the FX3 records at.

Current UHS-II SD Cards I Recommend

I update this list as new cards come out. The speeds are from my card reader tests, so they show what each card can do, not what the FX3 records at.

Sony FX3 Video Card Requirements

These are Sony’s requirements for the FX3. Sony notes that proxy recording may need a faster card, and that a U3/V30 SD card also works at 200 Mbps.

Standard Recording

Format	Max bitrate	Supported cards
XAVC HS 4K	280 Mbps	CFexpress Type A (VPG200+), or SDXC V60 or higher
XAVC S 4K	280 Mbps	CFexpress Type A (VPG200+), or SDXC V60 or higher
XAVC S HD	100 Mbps	CFexpress Type A, or SDHC/SDXC U3 or higher
XAVC S-I 4K	600 Mbps	CFexpress Type A (VPG200+), or SDXC V90
XAVC S-I HD	222 Mbps	CFexpress Type A (VPG200+), or SDXC V90

Slow Motion (S&Q)

Slow motion writes more data than the menu bitrate suggests, so Sony lists higher maximum bitrates for S&Q.

Format (S&Q)	Max bitrate	Supported cards
XAVC HS 4K	500 Mbps	CFexpress Type A (VPG200+), or SDXC V60 or higher (V90 may be needed at 120/100fps)
XAVC S 4K	560 Mbps	CFexpress Type A (VPG200+), or SDXC V60 or higher (V90 may be needed at 120/100fps)
XAVC S HD	500 Mbps	CFexpress Type A (VPG200+), or SDXC V60 or higher (V90 may be needed at 240/200fps)
XAVC S-I 4K	1200 Mbps	CFexpress Type A (VPG200+) only for slow motion
XAVC S-I HD	890 Mbps	CFexpress Type A (VPG200+), or SDXC V90 (CFxA required at 240/200fps)

Source: Sony ILME-FX3 Help Guide, “Memory cards that can be used.”

Choosing the Right Codec for Your Workflow

As an editor, I often get asked whether to shoot H.265 (XAVC HS) or H.264 All-Intra (XAVC S-I). XAVC HS is very efficient and fits more footage on cheaper V60 cards, but it’s heavy for your computer to decode, so expect stuttering on older machines. XAVC S-I compresses every frame individually and needs a V90 or CFxA card, but it plays back much more smoothly. Which one to use depends on the job: XAVC HS saves card space if you’re fine editing with proxies, and XAVC S-I gets you straight into the edit.

What Size Memory Card Do You Need for the Sony FX3?

For XAVC S-I 4K at 600 Mbps, Sony rates a 128GB SD card at about 25 minutes, so 256GB or larger makes sense if you shoot All-Intra. For XAVC HS 4K at 200 Mbps, a 128GB card holds about 1 hr 10 min, which is plenty for most shoot days. Sony’s maximum continuous recording time per clip is about 13 hours.

Sony FX3 Record Times

Format	Bitrate (60p/50p)	64GB SD	128GB SD	80GB CFxA	160GB CFxA
XAVC S-I 4K	600 / 500 Mbps	10 min	25 min	10 min	25 min
XAVC S-I HD	222 / 185 Mbps	30 min	1 hr 5 min	35 min	1 hr 15 min
XAVC HS 4K, XAVC S 4K	200 Mbps	35 min	1 hr 10 min	40 min	1 hr 25 min
XAVC HS 4K, XAVC S 4K	150 Mbps	45 min	1 hr 35 min	55 min	1 hr 50 min
XAVC HS 4K	100 Mbps	1 hr 10 min	2 hr 20 min	1 hr 20 min	2 hr 50 min
XAVC S HD	50 Mbps	2 hr 10 min	4 hr 30 min	2 hr 30 min	5 hr 10 min

Times are Sony’s estimates with proxy recording off. They run shorter than dividing card size by bitrate because the camera uses variable bitrate. For other settings, use my bitrate-to-record-time calculator.

Sony A7S III In-Camera Test Results: UHS-II SD Cards (Tested 2021)

These are the UHS-II SD cards I tested in the Sony A7S III, which shares the FX3’s sensor, processor, and card slots. The fastest V90 cards wrote 3–14 GB per burst before the camera slowed down, while V60 cards filled the buffer at about 1.4–2.1 GB.

Card	Class	A7S III write (MB/s)	Data per burst (GB)
Sony TOUGH G	V90	243	14.4
Delkin BLACK V90	V90	242	6.6
Angelbird AV PRO V90 MK II	V90	242	6.5
Kodak Ultra Pro V90	V90	242	6.2
Ritz Gear VideoPro V90	V90	241	5.0
Kingston Canvas React V90	V90	239	3.3
Delkin POWER V90	V90	235	5.4
Toshiba Exceria Pro	V90	220	9.0
Fujifilm Elite II	V90	164	2.7
Hoodman Steel 2000x	V90	158	2.6
ADATA Premier ONE	V90	134	2.0
ProGrade V90 (pre-Iridium)	V90	133	2.0
Transcend V90	V90	132	2.0
Lexar 2000x	V90	128	1.9
Sony E V60	V60	138	2.1
Angelbird AV PRO V60 MK II	V60	136	2.0
Amplim 2000x	V60	131	1.9
Lexar 1667x	V60	100	1.5
Hoodman Steel 1500x	V60	98	1.5
Amplim 1900x	V60	96	1.5
Sony TOUGH M	V60	96	1.5
ProGrade V60	V60	96	1.5
FreeTail Evoke Pro	V60	95	1.5
Delkin PRIME V60	V60	82	1.4

Fastest run per card. Data per burst includes the 2–4 shots I usually take after the buffer fills, so use it to compare cards, not as an exact buffer size. Older ProGrade V90 cards are pre-Iridium. I left out the older SanDisk Extreme PRO V90, which connected in UHS-I mode during this test (it still shows at the top of the chart); that version has since been replaced. UHS-I cards topped out at 78–80 MB/s (PNY Pro Elite, Delkin BLACK UHS-I, Kingston Canvas Select, and Kingston Canvas Go!), and the SanDisk Ultra wrote 27 MB/s.

Sony FX3 Specs

Spec	Sony FX3
Sensor	12.1MP full-frame CMOS
Processor	BIONZ XR
Card slots	Two slots, each CFexpress Type A or SD (UHS-II)
Continuous shooting	Up to about 10 fps (Hi+)
RAW file types	Compressed or Uncompressed
Highest bitrate	600 Mbps (XAVC S-I 4K), 1200 Mbps in S&Q
Max clip length	About 13 hours (Sony spec)
CFexpress Type B	Not supported

Sony FX3 Memory Card FAQ

Do I need CFexpress Type A for the Sony FX3?

Only for XAVC S-I 4K slow motion and XAVC S-I HD at 240fps or 200fps. A V90 SD card handles everything else, including 600 Mbps XAVC S-I at normal frame rates. I still recommend CFxA, since it costs about the same as V90 now and offloads much faster.

Do V60 SD cards work in the Sony FX3?

Yes, for XAVC HS and XAVC S at up to 280 Mbps, and for most slow motion in those formats. Sony doesn’t support V60 for XAVC S-I at all, and says you may need V90 for 4K at 120fps or HD at 240fps.

What is the fastest SD card for the Sony FX3?

In the Sony A7S III, which shares the FX3’s card slots, the Sony TOUGH G V90 was fastest at 243 MB/s, with the Delkin BLACK V90, Angelbird V90 MK II, and Kodak V90 all at 242 MB/s.

Do I need CFexpress 4.0 cards for the FX3?

No. The FX3 can’t use the extra speed of a CF 4.0 card, so it records the same as with a CF 2.0 card. The benefit is faster offloads with a 4.0 reader.

Can I mix a CFexpress card and an SD card in the FX3?

Yes. Each slot takes either type. For simultaneous backup recording, both cards need the same file system, so pair a CFxA card with an SDXC card (64GB or larger), not an SDHC card.

Are FX3 cards interchangeable with the A7S III and FX30?

Yes. All three use the same CFexpress Type A and UHS-II SD slots, so you can swap cards freely in a multi-cam setup. See my Sony FX30 card guide for the APS-C body.

How big a card do I need for XAVC S-I on the FX3?

Sony rates XAVC S-I 4K at about 25 minutes on a 128GB card or 160GB CFxA card, so 256GB or larger is the practical minimum if you shoot All-Intra all day.

More Sony Guides

• Best Memory Cards for the Sony A7S III
• Best Memory Cards for the Sony FX30
• Best Memory Cards for the Sony FX2
• Best Memory Cards for the Sony A7V
• CFexpress Type A card benchmarks
• SD card benchmarks
• Must-have Sony FX3 accessories
• Sony E-mount lens guide