Quick Summary
Both external hard drives and SD cards are portable storage devices that allow you to store and transport files. External hard drives generally have much higher storage capacities and are better for storing large amounts of data long-term. SD cards have lower storage capacities but are smaller and more portable. SD cards are a better choice if you need to frequently transfer small amounts of data between devices. For large photo, video, or music libraries, external hard drives are preferable.
Storage Capacity
One of the main differences between external hard drives and SD cards is storage capacity. External hard drives are available in capacities ranging from 500GB to 10TB or more. This allows you to store enormous amounts of data in one place. SD cards generally range from 2GB to 1TB. While 1TB SD cards are available, most consumer SD cards are 64GB or less. The limited capacity makes SD cards better for transferring smaller amounts of data.
| Storage Device | Common Capacities |
|---|---|
| External Hard Drive | 500GB – 10TB+ |
| SD Card | 2GB – 1TB |
If you need to store large media files like photos, videos, and music, an external hard drive is a better choice. The large capacities available let you consolidate all your media in one place. SD cards are not well-suited for storing thousands of media files due to their limited capacities.
Cost Per GB Comparison
In terms of cost effectiveness, external hard drives provide more storage capacity per dollar compared to SD cards. A 1TB external hard drive costs around $50, while a 1TB SD card costs around $180-$200. So you pay much less per gigabyte with an external hard drive. This makes them more cost effective for large storage needs. The portability and convenience of SD cards does come at a premium.
Transfer Speed
SD cards are designed for quick file transfers. The best SD cards have transfer speeds of 80-300MB/s. This makes them ideal for tasks like transferring photos from a DSLR camera to a computer. External hard drives usually have transfer speeds of 100-160MB/s. While not as fast as the fastest SD cards, external hard drive transfer speeds are fast enough for most storage and backup needs.
| Storage Device | Transfer Speed |
|---|---|
| External Hard Drive | 100-160MB/s |
| SD Card | 80-300MB/s |
The small size and portability of SD cards does give them an advantage for quickly transferring files between devices like cameras, phones, and computers. But the transfer speed of external hard drives is more than sufficient for backup, storage, and accessing your files from one device.
Durability and Reliability
External hard drives are better for long term storage because they are more durable and reliable than SD cards. External hard drives use durable platter-based or solid-state storage. SD cards use flash memory that is more prone to corruption or physical damage over time. External hard drives have failure rates of around 2-3% per year, while SD cards have failure rates of around 5-10% per year.
SD cards are prone to damage from drops, general wear and tear, water, magnets, and sudden power interruptions. A damaged SD card can easily become corrupted and unreadable. External hard drives are shock resistant and designed to withstand some drops. Always make sure to safely eject an external drive before removing it to prevent corruption. Set up automatic backups from your external hard drive for added data protection.
Longevity Comparison
With good care, external hard drives can easily last 3-5 years or longer. Write endurance for high quality SD cards is typically in the thousands. This means they can handle thousands of write/erase cycles before failure is a risk. This still puts their usable lifespan at around 2-4 years with frequent usage. For important files you want to store for many years, an external drive is the safer choice.
Ease of Use
SD cards have the advantage when it comes to portability and ease of use. Their small size lets them easily fit into cameras, phones, tablets, and laptops. You don’t need any external power source – just plug in the SD card and it’s ready to use. The lightweight, compact size makes them very convenient for transferring files between devices.
External hard drives are powered externally, usually via USB cable. This means you need access to power outlets to use them. They are also larger and bulkier to carry around. However, once hooked up, external hard drives are very easy to use. Most external drives come with backup software and utilities to help manage your files. The large capacity means all your files can be stored in one place rather than spread across multiple SD cards.
Speed of Accessing Files
When it comes to accessing your files, external hard drives are faster. Because they use a spinning disk or SSD storage, sequential read/write speeds are very fast. consumer SD cards use NAND flash storage, which has slower random read/write speeds. This means opening and accessing larger files can be quicker from an external hard drive.
Security
When it comes to security, external hard drives offer more protection for your sensitive files. Most external hard drives today offer built-in encryption to secure the entire drive. Software utilities included with the drive let you password protect and encrypt the drive. SD cards do not have built-in encryption features. To encrypt an SD card you would need to use third-party software.
External hard drives also offer more capacity for backing up your files. The large capacities available let you set up automatic backup software to continuously backup your computer’s hard drive. The limited capacity of SD cards makes them impractical to serve as a full system backup. SD cards are handy for transferring individual files between devices.
Backup Capabilities
A 1TB external hard drive is capable of storing:
- Backups for multiple computers
- Entire music, photo, and video libraries
- Many years worth of documents and other files
A 64GB SD card can only store:
- Files from a single project or trip
- Music, photos, or videos from a single device
- A system backup would require multiple SD cards
Compatibility
SD cards are widely supported across many devices and operating systems. The SD card standard is universally recognized making them plug-and-play on phones, cameras, tablets, and laptops. Most computing devices have built-in SD card slots. External card readers are also cheap and abundant for devices without dedicated slots.
External hard drives have broader compatibility than they used to, but there are some limitations. Most external drives today use a USB 3.0 interface that works with Windows and Mac computers right out of the box. Compatibility with smart TVs, game consoles, and mobile devices can vary depending on the drive format. Some external drives need to be reformatted before working with certain operating systems. Always check compatibility specs before purchasing an external hard drive.
OS Compatibility
| Storage Device | Windows | Mac | Smart TVs | Mobile Devices |
|---|---|---|---|---|
| External Hard Drive | Yes* | Yes* | Limited | Limited |
| SD Card | Yes | Yes | Yes | Yes |
*May require reformatting depending on initial format
Performance With Large Files
The high data transfer speeds of external SSD or HDD drives make them better suited for working with large files. The fast sequential read/write speeds allow for smooth playback of high resolution video. Fast transfer speeds also help improve workflow efficiency when working with large photo or video files. SD cards are not ideal for holding large files due to slower transfer speeds in most models.
SD cards use flash storage so sequential read/write operations will be significantly slower than an SSD or HDD external drive. This means longer transfer times when moving GB sized files to or from the SD card. Performance will drop if the card is close to full capacity. Larger capacity SD cards improve sequential performance but max out around 300MB/s. External drives are a better solution for quickly accessing frequently used large files.
Editing Large Videos
When editing large high resolution video files, footage will load noticeably faster from an external SSD compared to an SD card. Scrubbing through video in the timeline will be more responsive. Quicker load times and smoother playback will translate to a better editing experience. Working from large SD cards will result in longer project load times and choppy playback.
Storing Files Long Term
For long term storage spanning many years, external hard drives are preferable to SD cards. As mentioned earlier, external drives are engineered for greater durability and reliability. Continuously writing data to an SD card will cause it to wear out after around 2-4 years. External SSD drives can last up to 10 years thanks to better flash memory controllers.
Mechanical HDD external drives have moving platters that are vulnerable to shock damage. But kept in a secure place they can provide reliable storage for 5 years or more. Use an external drive dedicated to long term storage. Always handle the drive carefully and keep it in a safe place for maximum longevity.
Reformat your external drive every 2-3 years when storing for the long term. Reformatting cleans up various drive errors that can slowly accumulate over time. This helps maintain peak performance and reduces the likelihood of file corruption.
Archive Storage
A large capacity external hard drive is suitable for archiving old files you want to keep accessible. For example, you could store all documents from the past 10 years on a high capacity drive. This removes clutter from your primary computer while still keeping the files accessible if needed.
Conclusion
In the external hard drive vs SD card debate, external drives are better suited for long term storage and housing large files and media libraries. The higher capacities, faster speeds, and lower cost make them a versatile home for all your data. SD cards are ideal for conveniently transferring smaller files between devices. Their pocket-size portability can’t be beat. The best solution may be utilizing external hard drives for storage and SD cards for transfer.
When choosing an external drive, get the highest capacity within your budget to future-proof yourself. Always eject the drive safely before disconnecting. Encrypt and password protect the drive for security. Follow manufacturer guidelines for care and longevity. With proper use, it can reliably store all your important files for years to come.
