# item.guide
Side-by-Side Comparison Memory Cards

CFexpress vs. SD Card

Comparing 2 standards across 13 specifications. 13 key differences identified.

Comparing:
CFexpress
SD Card

CFexpress is an ultra-high-speed removable solid-state storage media standard developed by the CompactFlash Association (CFA). Built directly on the PCI Express (PCIe Gen 3/Gen 4) physical bus and NVM Express (NVMe) command set, it is the dominant storage medium for high-end professional digital cinema, mirrorless photography, and broadcast video.

View full CFexpress spec sheet →

The SD Card (Secure Digital) is the global standard removable flash memory form factor established in 1999 by Panasonic, SanDisk, and Toshiba (SD Association). Measuring 32.0 × 24.0 × 2.1 mm, it spans capacity generations from original SDSC (up to 2GB) and SDHC (up to 32GB) to SDXC (up to 2TB) and SDUC (up to 128TB).

View full SD Card spec sheet →

Specification Comparison Table

13 Parameters
Parameter / Spec
Governing Body
CompactFlash Association (CFA) SD Association (SDA)
Underlying Storage Architecture
PCI Express (PCIe Gen 3 / Gen 4 / Gen 5) + NVM Express (NVMe v1.3/1.4)
Type A Dimensions & Bus
20.0 × 28.0 × 2.8 mm | 1-lane PCIe (1 GB/s PCIe 3.0 / 2 GB/s PCIe 4.0)
Type B Dimensions & Bus
38.5 × 29.6 × 3.8 mm | 2-lane PCIe (2 GB/s PCIe 3.0 / 4 GB/s PCIe 4.0)
Type C Dimensions & Bus
54.0 × 72.0 × 4.4 mm | 4-lane PCIe (4 GB/s PCIe 3.0 / 8 GB/s PCIe 4.0)
Type B XQD Compatibility
Physically identical exterior shell to Sony XQD (host backward-compatible via firmware)
Operating Power Tiers
Up to 1.7W (Type A) / Up to 3.0W (Type B) / Up to 6.0W (Type C)
Physical Dimensions
32.0 mm × 24.0 mm × 2.1 mm
Pin Configurations
9 pins (UHS-I / Legacy) / 17 pins (UHS-II / UHS-III dual-row) / 19 pins (SD Express)
Capacity Standards
SDSC (≤2GB), SDHC (4–32GB), SDXC (64GB–2TB), SDUC (2TB–128TB)
Standard File Systems
FAT12/16 (SDSC), FAT32 (SDHC), exFAT (SDXC / SDUC)
Operating Voltages
2.7V–3.6V (Standard) / 1.8V (UHS-I/II signal voltage)
Mechanical Features
Write-Protect slide notch (left edge), 45-degree polarized corner keying