While the FX3 shares its body design with its sibling, the FX30, the full-frame sensor in the FX3 demands a different approach to media handling. Because the FX3 is often used as a primary ‘A-Cam’ for high-bitrate narrative work, choosing a card that supports Full Frame 4K 120p or the high-end 600 Mbps recording rate without thermal throttling is essential. This camera, after all, is Netflix-approved and part of Sony’s professional cinema line.
Since the Sony FX3 supports both CFExpress Type-A and SD Memory cards, I would recommend CFExpress cards for this one.
Table of Contents
Sony FX3 Memory Card Recommendations: Quick Pick
The Lexar Silver Type A is one of the best-value memory cards for the Sony FX3, as it lets you do everything with CFeA cards with a 200MB/s sustained guarantee and is now priced very similarly to UHS-II V90 cards; CFxA is now the better buy for this camera.
Also, new CF4.0 Type-A cards have much faster read and write speeds, which can be useful with file transfers. However, pay attention to sustained speeds, as that’s the most important metric for video recording. See all the CFexpress Type-A benchmarks to see how the latest cards perform.
| Recommended For Sony | USB Write | USB Read | Check Price | |
|---|---|---|---|---|
| CFExpress Type-A | Hide | |||
| Sony G Tough CF4.0 240/480/960/1920GB | B&H | |||
| Sony M Tough 960GB | Sony M Tough CFExpress Type-A Review | Amazon / B&H | ||
| Sony G Tough 80/160/320/640GB | Sony G Tough CFExpress Type-A Review | 658 | 847 | Amazon / B&H |
| Lexar Gold 80/160GB/320GB | 825 | 886 | Amazon / B&H | |
| Delkin Black 80GB | 654 | 845 | Amazon / B&H | |
| ProGrade Iridium CF4.0 480-960GB | 1272 | 1532 | Amazon / B&H | |
| Pergear Standard 256GB | Pergear Standard 256GB CFxA Review | 768 | 812 | Amazon |
Why I Recommend CFexpress Type A for the FX3
While the FX3 can take SD cards, I recommend exclusively using CFexpress Type A for professional projects.
CF 4.0 & Post-Production: We are seeing new CF 4.0 cards. While they don’t change how the camera records, they will cut your offload times by 50% if you use a USB4 or Thunderbolt reader. For a professional editor, that time saved is worth the investment.
The Sustained Speed Advantage: Unlike SD cards, which often “dip” in speed during long takes, CFexpress Type A is designed for the heat and data throughput of 600Mbps video.
All-Intra (XAVC S-I): If you want to shoot in the All-Intra codec—which I prefer for its ease of playback in the edit suite—you need a card with a high minimum sustained speed. The Lexar Silver Series is currently the best value here, offering Pro-level speeds at a consumer price point.
UHS-II V90 SD Memory Cards – Like the CFexpress cards, the SD UHS-II V90 cards will also allow you to use all the video modes of the Sony FX3; however, with CFexpress Type-A cards now often the same price or less, V90 SD cards don’t make as much sense for this body, and generally, it would be better to either spend a little more on a CFexpress card or go for one of the budget options.
UHS-II V60 SD Memory Cards – If you’re recording in H.265 (XAVC HS), you can use V60 UHS-II memory cards for significant cost savings. However, you will be limited to some of the S&Q slow-motion modes; the regular slow-motion settings will still work fine.
Sony FX3 Specs
| Sensor: 12MP Full-Frame Exmor R BSI CMOS Sensor Processor: BIONZ XR Image Processor Memory Card Slots: 2 UHS-II / 2 CFe A Continuous Shoot: 10fps Est. Buffer Size: — RAW Shots To Fill Buffer: 1000 Frames Max Memory Card Size: Unlimited 4k Datarate: H.265 280Mbps / H.264 600Mbps |
The FX3 shares the same 12MP BSI sensor and BIONZ XR processor as the A7S III, so CFxA performance translates directly — including the bottomless stills buffer that makes burst benchmarks impossible to run on this body.
Best Memory Cards For 4k Video
Sony FX3 Video Specs & Recording Modes
With the Sony FX3, various record modes use different codecs. It gets a little complicated, so here is the breakdown.
What’s new on the Sony FX3 compared to older Sony cameras is XAVC HS and XAVC S-I.
Choosing the Right Codec for Your Workflow
As an editor, I often get asked: Should I shoot H.265 (XAVC HS) or H.264 (XAVC S-I)? >
XAVC HS (H.265): This is incredibly efficient, allowing you to fit more footage on cheaper V60 SD cards. However, H.265 is a “heavy” codec for your CPU to decode. If you’re on an older MacBook, expect some stuttering in the timeline.
XAVC S-I (All-Intra): The gold standard for quality. It compresses every frame individually. It requires a faster card (V90 or CFexpress), but it’s much easier for your computer to play back. If you want a smooth editing experience without making proxies, this is your codec.
Multi-Cam Shooters: If you use the FX3 as your A-Cam and the FX30 as your B-Cam, good news: they use the exact same media. You can swap cards freely between bodies. Check out my Sony FX30 Media Compatibility List.
Sony FX3 Recording Specs & Details
Record Limit: Unlimited
Audio File Format: AAC, Linear PCM
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4k Recording Modes |
Sony FX3 Record Times – Memory Card Capacity
This table shows the different recording modes and the time required for each card size. To get your own numbers, I have to build a bitrate-to-time converter.
| Sony FX3 Record Times | 64GB | 80GB | 128GB | 160GB | 256GB | 512GB |
| 4k | ||||||
| 4k 600Mbps | 75MB/s H.264 | 14min | 18min | 28Min | 36min | 57min | 114min |
| 4k 280Mbps | 35MB/s H.265 | 30min | 38min | 61min | 76min | 122min | 244min |
| 4k 200Mbps | 25MB/s | 43min | 53min | 85min | 107min | 171min | 341min |
Other Guides and Gear Recommendations
Now that your media is sorted, you might want to look into screen protectors or audio gear. I’ve compiled a list of the must-have gear for the Sony FX3 to help you finish building out your kit.
A Note on Lens Choice: If you plan to use the FX3’s ‘Focus Breathing Compensation’ feature, you are limited to specific Sony lenses. However, for standard shooting, you have hundreds of options. Check my Ultimate Sony E-Mount Lens Guide to see which third-party lenses from Sigma or Tamron might offer better value for video work.
Sony FX3 Memory Card FAQ
Do SD cards cover all recording modes on the FX3?
V90 UHS-II covers everything the FX3 can do. V60 covers all H.265 (XAVC HS) modes and most H.264 modes but gets marginal at 600Mbps XAVC S-I during long takes. For a primary cinema camera where you’re running extended takes at maximum bitrate, CFxA’s consistent sustained write speed is the safer choice — and it now costs about the same as V90.
Are FX3 cards interchangeable with the A7S III or FX30?
Yes — all three cameras use the same CFexpress Type A and UHS-II SD slots. If you run a multi-cam setup with FX3 and FX30, or FX3 and A7S III, you can swap cards freely between bodies. One shared pool of CFxA cards across the kit.
Do I need CF 4.0 cards for the FX3?
No. The FX3 records at the same speed with CF 4.0 as with CF 2.0 — the camera can’t take advantage of the extra write bandwidth. Where CF 4.0 matters is offload speed: with a CF 4.0 reader and a USB4 or Thunderbolt connection, transfer times drop significantly compared to older readers. If fast offloads matter to your workflow, the reader is the upgrade, not necessarily the card.
What’s the real difference between CFxA and V90 SD for cinema work?
For short takes, almost nothing. The difference shows up in sustained performance during long recording sessions — SD cards can dip below their rated write speeds when running hot, while CFxA cards maintain consistency. On a run-and-gun shoot with short clips that barely matters. On a controlled narrative set with long takes in 600Mbps XAVC S-I, CFxA is the more reliable tool.
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