
Kingston 4GB microSDHC Card
Score: 53/100
Lexar High-Performance 633x 256GB
Score: 60/100Rankings

Lexar's 256 GB 633x microSDXC offers up to 100 MB/s read speed, a V30 rating, and includes a micro-SD to SD adapter for versatile use. Its slower 45 MB/s write speed and lack of waterproofing limit high-end video applications. Suitable for smartphones, tablets and action cameras where large capacity and broad compatibility are priorities.

The Kingston 4 GB microSDHC Class 4 card offers robust waterproof and shockproof protection with a lifetime warranty, making it reliable for basic storage needs. However, its low 4 MB/s transfer rate and limited 4 GB capacity restrict performance for modern high-resolution media. Best suited for users of older devices needing a small, durable card.
| Attribute | ![]() | ![]() |
|---|---|---|
4 GB | 256 GBbest | |
4 MB/s | 100 MB/sbest | |
— | 45 MB/sbest | |
| ↓ lower better | 25 gbest | 453.6 g |
| ↓ lower better | 1 mmbest | 1.02 mm |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Storage(1) | ||
Capacity (GB) | 4 GB | 256 GB |
Performance(2) | ||
Read Speed (MB/s) | 4 MB/s | 100 MB/s |
Speed Class | Class 4 | C10 |
Design(3) | ||
Form Factor | microSDHC | microSDXC |
Weight (g) | 25 g | 453.6 g |
Thickness (mm) | 1 mm | 1.02 mm |

Products in the top-left offer the best value (high score, low price).

Professional testing shows the Lexar 633x card delivers real-world read speeds near 97 MB/s and write speeds around 69 MB/s, surpassing its advertised specifications and confirming its suitability for 4K video capture. Reviewers acknowledge its solid mid-range performance but point out that newer Lexar BLUE models provide higher peak speeds, making the 633x less compelling for users seeking top-tier throughput.
Everyday users praise the large 256 GB capacity, the included SD adapter for easy file transfer, and the peace of mind from the lifetime warranty. They also highlight the card's reliable 4K video performance and compatibility with a wide range of devices. However, some users note the write speed feels modest compared to newer offerings, and the lack of UHS-II support limits its appeal for high-end professional use.


