Solid state drives (SSDs) and hard disk drives (HDDs) are two of the most common types of computer storage devices. Both have their own advantages and disadvantages when it comes to factors like speed, durability, and cost. One of the biggest differences between SSDs and HDDs is the cost per gigabyte (GB) of storage space.
SSD Cost Per GB
SSDs are generally more expensive per GB than HDDs. There are a few reasons for this:
- More complex manufacturing process – SSDs use NAND flash memory chips rather than magnetic platters like HDDs. Producing these chips requires more precision and quality control, driving up costs.
- Higher material costs – The raw materials for flash memory and SSD controllers are more expensive than those for HDDs.
- Lower production volumes – HDDs are produced in much higher volumes than SSDs, allowing for economies of scale to reduce per unit costs.
The average cost per GB for consumer SSDs currently ranges from around $0.15 to $0.50. Enterprise and industrial SSDs designed for heavy workloads can cost between $0.50 and $2.00 per GB. Some factors that affect SSD cost per GB include:
- Drive capacity – Larger capacity SSDs typically have a lower cost per GB.
- Form factor – Smaller form factors like M.2 SSDs often cost more per GB than 2.5″ SSDs.
- Interface – Newer interfaces like PCIe 4.0 have a premium cost over older SATA interfaces.
- Endurance rating – SSDs built for heavier write workloads require more expensive NAND chips.
- Brand – Well known brands like Samsung and WD carry a price premium over lesser known brands.
Here are some examples of current SSD costs per GB from popular models:
| SSD Model | Capacity | Price | Cost per GB |
|---|---|---|---|
| Samsung 870 EVO SATA SSD | 1TB | $99.99 | $0.10 |
| WD Blue SN570 NVMe SSD | 1TB | $84.99 | $0.08 |
| Samsung 980 Pro PCIe 4.0 NVMe SSD | 1TB | $149.99 | $0.15 |
HDD Cost Per GB
HDDs have a much lower cost per GB compared to SSDs. Current prices range from around $0.02 on the low end to $0.05 on the high end. Some factors affecting HDD cost per GB include:
- Drive capacity – Like SSDs, higher capacity HDDs typically have lower cost per GB.
- Form factor – 3.5″ desktop HDDs are cheaper per GB than 2.5″ notebook HDDs.
- RPM speed – Faster 7200 RPM HDDs are slightly more expensive than 5400 RPM models.
- Cache size – More cache memory adds some cost.
- Interface – SATA models are the most common and cost effective. SAS models designed for enterprise use carry a premium.
Here are some current examples of HDD costs per GB from popular models:
| HDD Model | Capacity | Price | Cost per GB |
|---|---|---|---|
| Seagate BarraCuda Compute 3.5″ HDD | 2TB | $47.99 | $0.02 |
| WD Blue 3D NAND 2.5″ SATA SSD | 2TB | $199.99 | $0.10 |
| Toshiba N300 NAS 3.5″ HDD | 12TB | $339.99 | $0.03 |
SSD vs. HDD Cost Comparison
When you compare the cost per GB of HDDs and SSDs directly, SSDs are still about 3-5 times more expensive per unit of storage. However, the gap has narrowed significantly over the past decade. In 2010, SSDs cost around $2.00 per GB while HDDs were only $0.05 per GB – a massive 40x price difference!
Improving NAND flash manufacturing processes and increasing adoption have steadily driven SSD prices down over time. Meanwhile, HDD costs per GB have remained fairly steady over the past decade. Here’s a chart comparing how the average SSD and HDD costs per GB have changed since 2010:
| Year | SSD Cost Per GB | HDD Cost Per GB |
|---|---|---|
| 2010 | $2.00 | $0.05 |
| 2015 | $0.50 | $0.04 |
| 2020 | $0.20 | $0.03 |
| 2023 | $0.15 | $0.02 |
While HDDs maintain the clear advantage in cost per GB, the lower power consumption, performance, durability, and form factors of SSDs make them worth the premium cost for many users. Ultrabooks, gaming PCs, and high performance servers rely on SSD speed to deliver better experiences, even at a higher data storage cost.
Factors that Influence Cost Per GB
There are a few key factors that determine the cost per GB for both SSDs and HDDs:
Manufacturing Process
The manufacturing process used to produce NAND flash memory chips and HDD platters has a direct impact on per unit costs. Incremental advancements like 3D NAND stacking and larger platter sizes have reduced costs over time.
Adoption Rates
As SSDs gain more mainstream adoption, larger production volumes allow manufacturers to take advantage of economies of scale. More HDD and SSD competition also puts downward pressure on prices.
Component Prices
Prices for key components like DRAM and NAND flash memory influence the final SSD cost. Shortages in NAND and DRAM can drive SSD prices up while oversupply can lower prices.
Drive Capacities
Higher capacity drives benefit from lower cost per GB. As drive capacities increase over time, this puts downward pressure on cost per GB.
Interface
Newer and faster interfaces like PCIe 4.0 and SATA III allow for improved SSD performance but at a higher cost per GB compared to older interfaces.
SSD vs. HDD Pricing Outlook
Industry analysts expect SSD pricing to continue declining over the next several years, but not as aggressively as in the past decade. HDD pricing is expected to remain steady near current levels. NAND flash manufacturers are approaching technical and economic limits that prevent further dramatic cost reductions. Since HDD technology is fairly mature, only modest improvements in HDD cost per GB are expected going forward.
Here are some predictions for SSD and HDD cost per GB trends over the next 5 years:
- SSD cost per GB will decline from $0.15 today to around $0.10 by 2025
- High capacity HDDs will remain around $0.02 per GB through 2025
- SSDs will achieve cost parity with HDDs for bulk data storage sometime between 2025-2030
In summary, SSD prices will continue dropping slowly but HDDs will still maintain the advantage for bulk data storage needs. For applications where performance, ruggedness, power efficiency, and form factor are critical, SSDs will remain worth the premium despite higher cost per gigabyte.
Conclusion
The cost per GB of storage is one of the main factors to consider when choosing between SSD and HDD storage. While HDDs are around 3-5 times cheaper per GB than SSDs, the performance and durability benefits of SSDs make them the preferred choice for many demanding applications despite the higher price.
Improved manufacturing techniques and increased adoption rates have steadily driven down SSD prices over time, but HDDs maintain the advantage in cost-effective bulk data storage. Moving forward, SSDs are expected to continue closing the pricing gap with HDDs, but parity is not expected until the late 2020s at the earliest.
When planning data storage purchases, businesses and individuals should evaluate their performance, capacity, and budget requirements. HDDs are appropriate for archival data and backups, while SSDs are better suited to mission-critical systems and primary data storage. Considering the total cost of ownership rather than just upfront costs can help determine the optimal storage technology as well.