Independent testing
How much independent testing exists for each memory card
Of the 6 memory cards we track, 5 have been physically measured by at least one independent lab. Below is every one, ordered by how much independent hands-on evidence stands behind it — densest first.
A coverage record, not a ranking of which is best.
| Product | Independent labs | Metrics measured | Outlets on record |
|---|---|---|---|
| Lexar Professional 1667x SDXC UHS-II 128GB | 1 | 1 | 1 |
| Samsung EVO Select microSDXC 256GB (2024) | 1 | 1 | 1 |
| Samsung PRO Plus Full-Size SD 256GB (2023) | 1 | 1 | 1 |
| SanDisk Extreme PRO microSDXC UHS-I 512GB | 1 | 1 | 1 |
| Sony TOUGH SF-G Series UHS-II SD 128GB | 1 | 1 | 2 |
| SanDisk Extreme microSDXC UHS-I 256GB | 0 | 0 | 1 |
Each figure is a count of what independent testers actually did — how we count. A low count means little independent evidence has been gathered yet, never that a product is worse. See also the Memory Cards buying guide and the reviewers we cite.