A1 vs A2 (Random IOPS)

This is the number that matters most on a Pi. A2 cards handle far more small random reads/writes per second than A1 — which is exactly what a running OS, package manager and apps do. For a desktop Pi OS, always pick A2.

Speed Class (U3 / V30)

U3 and V30 guarantee a minimum sustained write of 30MB/s. That’s plenty for OS use and important if your Pi records video or logs data continuously. Ignore the flashy peak number and check the guaranteed floor.

Capacity

16GB is the bare minimum for Pi OS Lite (headless). 32GB is a comfortable sweet spot, and 64–128GB suits a full desktop, media centre or retro-gaming build. Bigger cards also tend to have slightly better write endurance.

Endurance

Every flash cell has limited write cycles. For always-on projects that write constantly — CCTV, dashcams, data loggers — a High-Endurance or PRO Endurance card lasts far longer than a standard performance card.

Genuine & Reliable

Card failure is the #1 cause of a “dead” Pi. Buy branded cards from reputable sellers, avoid suspiciously cheap high-capacity deals, and verify real capacity with F3/h2testw. A trusted 32GB beats a fake 256GB every time.

The SanDisk Extreme is the smart-money pick: it keeps the all-important A2 rating and nearly matches the Extreme Pro’s read speed (190MB/s), but usually costs noticeably less. Sustained write speed is lower than the Pro, so it’s not the pick for heavy continuous recording — but for a general-purpose Pi 4/Pi 5 running a desktop, home server or project, it hits the sweet spot of performance and price.

The Samsung EVO Plus is the value champion — a reliable, widely-available card at a friendly price with 160MB/s reads. It’s a great choice for a Pi Zero, a media centre, a Pi 400 or any build where you want dependable storage without paying premium-card money. Just note its random-IOPS (app) performance isn’t as strong as the A2 cards above, so a heavy desktop OS will feel a little less snappy — for a Lite/headless setup or light use, you won’t notice.

The Kingston Canvas Go! Plus is a superb A2 card at up to 200MB/s, and it’s our pick for RetroPie, Lakka, Batocera and Recalbox builds. Emulation front-ends hammer the card with lots of small random reads as they scan libraries and load ROMs, and the A2 rating keeps menus and games loading fast. With a lifetime warranty and capacities to 1TB, it’s also a great general-purpose Pi card that often undercuts the big two on price.

The official Raspberry Pi microSD card is engineered and tested specifically for Pi hardware, with support for command queuing (CQ) and both DDR50 and SDR104 bus modes — hitting up to 5,000 read IOPS on a Pi 5. It’s the true plug-and-play option: you can buy it blank or pre-loaded with Raspberry Pi OS, so it boots the moment it arrives. Default capacities are smaller (32/64/128GB), but for a guaranteed-compatible, no-surprises card, nothing is safer.

The Kingston Canvas Select Plus is the card to grab when you’re buying in bulk or building on a tight budget — think classroom kits, Pi Zero clusters or simple headless projects. It’s an A1 card at 100MB/s, so it’s reliable and perfectly fine for Pi OS Lite and light workloads. It won’t feel as fast as an A2 card on a full desktop, but for the money it’s one of the most dependable cheap cards you can buy.

If your Pi runs a camera, dashcam, security recorder or data logger that writes continuously, a standard performance card will wear out fast. The SanDisk High Endurance is built for exactly this — rated for tens of thousands of hours of continuous recording. It’s not the fastest card for a desktop OS, but for a write-heavy always-on project it will far outlive an Extreme or EVO Plus, saving you from mid-project card failures.

The Samsung PRO Endurance takes longevity even further, rated for up to 140,000 hours of recording on the largest capacities. It’s the card for a Pi that logs sensor data around the clock, runs a long-term time-lapse, or acts as a home CCTV recorder — anywhere the card is written to constantly for years. Speed is modest, but endurance and data safety are the whole point, and Samsung backs it with a long warranty.

The Lexar Professional 1066x is an A2 card with strong 160MB/s read and up to 120MB/s write speeds, and it’s frequently sold in 2-packs — making it a great-value way to card up multiple Pis at once, or keep a ready spare for backups. It’s water-, shock-, vibration- and X-ray-proof, and the A2 rating keeps a Pi desktop responsive. If you run several boards or like having a cloned backup card on hand, the multi-pack pricing is hard to beat.

Running a full desktop OS?

Get an A2 card — the SanDisk Extreme Pro or Samsung PRO Plus. Random IOPS make the desktop feel fast.

On a budget or buying in bulk?

The Samsung EVO Plus for value, or the Kingston Canvas Select Plus for the cheapest reliable option.

Building a retro-gaming Pi?

The A2 Kingston Canvas Go! Plus loads ROMs and menus fast in RetroPie, Batocera and Lakka.

Recording or logging 24/7?

Choose a SanDisk High Endurance or Samsung PRO Endurance — built to survive constant writes.

Total beginner?

The official Raspberry Pi card, pre-loaded with Pi OS, is the safest no-fuss way to get booted.

Running several Pis?

The Lexar Professional 1066x 2-pack is a cost-effective way to card up multiple boards or keep a spare.

What size microSD card do I need for a Raspberry Pi?

16GB is the practical minimum for Raspberry Pi OS Lite (headless). 32GB is the comfortable sweet spot for most projects and leaves room to grow. Step up to 64–128GB for a full desktop, a media centre (Kodi/Plex), or a retro-gaming build with lots of ROMs. Going bigger than 128GB rarely helps a Pi unless you’re storing large media locally — and at that point a USB SSD is often the better call.

Does a faster 200MB/s card make my Pi faster?

Only partly. The Raspberry Pi’s own microSD slot caps out well below those numbers — roughly 50MB/s on the Pi 4 (DDR50) and about 90MB/s on the Pi 5 (SDR104) — so you’ll never hit 200MB/s on the Pi. What actually makes a Pi feel faster is random-access performance (the A2 rating), which speeds up booting, app launches and package installs. The big sequential number mainly helps when you flash or back up the card on a PC. Bottom line: buy A2, and don’t overpay purely for a higher headline read speed.

What’s the difference between A1 and A2, and does it matter for Pi?

A1 and A2 are “Application Performance Class” ratings that guarantee minimum random read/write IOPS — A1 guarantees 1,500 read / 500 write IOPS, while A2 guarantees 4,000 / 2,000. Because a running operating system does constant small random reads and writes, A2 makes a real, noticeable difference to how snappy a Pi desktop feels. For a full Pi OS desktop, choose A2. For a headless Lite install or a simple appliance, A1 is perfectly adequate and cheaper.

How do I avoid fake or counterfeit microSD cards?

Counterfeits are the biggest cause of “my Pi keeps corrupting”. Buy branded cards sold and shipped by the manufacturer or a reputable retailer, and be very suspicious of huge capacities at tiny prices. When your card arrives, verify its real capacity and health with a free tool like F3 (Linux/Mac) or h2testw (Windows) before trusting it with a project — a fake 256GB card that’s really 32GB will silently lose your data once it fills up.

Should I use a microSD card or boot from an SSD?

A quality A2 microSD is perfectly good for the vast majority of Pi projects and is the simplest option. But if you’re running a 24/7 home server, a database, a NAS or anything with heavy, constant writes, booting from a USB 3.0 SSD (fully supported on Pi 4 and Pi 5, and via NVMe on Pi 5) gives you far better speed and dramatically longer lifespan. Many people keep an SD card for the OS and add an SSD for data, or move to full SSD boot for serious workloads.