Can I use my computer while it is backing up to an external hard drive?

External hard drives provide a convenient way to store and backup large amounts of data. They can be connected to computers via USB, Thunderbolt, or other interfaces. When backing up to an external drive, it copies files from the internal drive to the external one. This safeguards important data in case the computer’s internal drive fails or is lost, stolen, or damaged.

A common question that arises is whether you can continue using your computer normally while it is backing up data to the external drive. There are some factors to consider, as actively using the computer during backup can impact performance and lead to potential issues. However, with some precautions, it is generally possible to safely use your computer in limited capacity during an external drive backup.

Potential Issues

Using your computer while it is backing up data to an external hard drive does come with some potential issues to be aware of:

File corruption/failed backup – If you are reading or writing data to the drive that is being backed up, it can interfere with the backup process and cause file corruption or a failed backup. The backup software is trying to make an exact copy of your drive, so if the data is changing while it’s copying, it can result in errors. This is the biggest risk to be aware of. If the backup fails or the files get corrupted, you can be left without the backup copy you were counting on.

Decreased performance – The backup process can take up a lot of your computer’s resources, like CPU, memory, and disk usage. So your computer may run slower and be more sluggish, especially for tasks like streaming video, gaming, or using resource-intensive programs. The performance impact depends on the size of the backup and computer specs.

Hard drive overheating – When your backup drive spins constantly to write all that data from your computer, it can cause the external hard drive to overheat, especially if the backup drive is running at full capacity for an extended time. An overheated external drive can lead to potential hardware failure.

Mitigating Factors

There are a few factors that can help mitigate performance impacts when using your computer during a backup:

For less demanding tasks like web browsing or word processing, you may notice little to no effect on computer performance during a backup. However, for more resource-intensive tasks like gaming, video editing or 3D modeling, the backup may cause slowdowns.

Optimizing your backup software settings can help minimize performance hits. According to BackupAssist, disabling the backup estimate and skipping file verification can improve speed [1]. Backblaze users on Reddit recommend testing different thread count settings to find the optimal balance of performance vs. backup speed [2].

Overall, lighter computer use will reduce the impact of backups, and optimized software settings can smooth performance. But for demanding tasks, slowdowns may still occur during active back ups.

Best Practices

When backing up your computer while still wanting to use it, there are some best practices you can follow to help ensure a smooth process:

Close any unnecessary programs during the backup process to free up computing resources. The backup will run faster and put less strain on your computer if other memory-intensive programs are not also running.

Avoid taxing computing tasks like gaming, video editing or running multiple programs simultaneously during the backup. Stick to light activities like web browsing or word processing. [1]

Adjust your backup software settings for optimal performance. Set it to utilize less computing resources, turn off non-essential functions like file compression during backup, or schedule it for times you are not using the computer. This allows you to use the computer normally while the backup runs in the background.

When to Avoid Use

There are certain scenarios when it’s best to avoid using your computer during a backup to an external hard drive:

During initial full backups – The first backup will transfer the maximum amount of data and fully utilize disk and system resources. Using the computer during this time will significantly slow down both the backup and normal computer use. According to this Quora post, certain functionality will slow down especially reading from the same drives that are backing up.

With older/slower hard drives – If you are backing up to an older or slower external drive, the backup process will be bottlenecked by the drive speeds. Using the computer during this time will make the experience frustratingly slow.

With high CPU/RAM-intensive tasks – If you need to use the computer for CPU or RAM intensive tasks like gaming, video editing or 3D modeling, it’s best to avoid starting a backup at the same time. Both the task and backup will compete for computing resources and slow everything down according to this Acronis forum thread.

Use with Caution

Although using your computer while it’s backing up is generally okay, there are some tasks that can significantly slow down the backup process or vice versa. Activities like streaming media, gaming, and video editing tend to require a lot of computing resources and can interfere with backup performance.

Streaming high resolution video or using services like Netflix, Hulu, YouTube etc. uses a large amount of network bandwidth as the media is being downloaded and buffered continuously. This leaves less bandwidth available for the backup to transfer data, resulting in slower speeds (1). Gaming also places heavy demands on the CPU, GPU, RAM and network which could impact backup speeds, especially for graphics intensive games. The constant reading and writing of game assets competes with the backup drive access (2).

Video editing is very resource intensive due to the large file sizes and need to render previews and output. Complex edits require high CPU usage and drive access that could dramatically slow down a backup in progress. Scrubbing through the timeline and rendering will be sluggish (3). It’s better to avoid video editing while backing up and schedule backups around editing sessions.




Safe Light Use

Light computer use such as email, web browsing, and office applications is generally safe during a backup process. The backup software is designed to work seamlessly in the background without interrupting normal usage [1]. Just be aware of the following:

Email – Opening, reading, and sending emails typically has minimal impact during a backup. However, downloading large email attachments could temporarily slow down the backup process.

Web Browsing – Casual web surfing should not interfere with a backup in progress. But streaming video or downloading large files could compete for disk resources and slow down the backup.

Office Applications – Light office work like writing documents or spreadsheets will not disrupt a backup. But saving large files frequently could potentially slow it down.

Overall, normal computer use is fine during most backups. Just avoid demanding tasks that heavily tax the disk. Also be prepared for slightly slower performance until the backup completes [2].



Maximizing Performance

When using your computer during a backup process, it’s important to maximize performance so the backup can complete as quickly as possible. Here are some tips for improving backup speed and efficiency:

Upgrade to a faster external drive. Solid state drives (SSDs) offer much faster read/write speeds compared to traditional hard disk drives (HDDs). Investing in an SSD as your backup destination will significantly reduce backup times. Choose an external SSD with high read/write speeds for optimal performance (Source).

Schedule backups during idle times. Set your backup software to run during periods when you are not actively using your computer, such as overnight. This avoids competition for disk access and system resources between your applications and the backup process.

Adjust software settings. Some backup programs allow you to modify settings like compression level, thread count, and data block size. Optimizing these settings based on your system specs can improve backup speeds. Disable settings like file-level backups if maximum throughput is needed (Source).


Fixing failed or corrupted backups is an important troubleshooting step when using your computer during backups. The backup software may fail due to bad input, exceeded resource limits, or software glitches according to the Backup Failure: Why It Occurs & How to Prevent It article ( Running chkdsk /f /r can fix errors on the hard drive according to Microsoft (

Another issue to watch for is hard drive overheating from excessive activity during backups. Make sure the external drive has adequate ventilation and cooling. If needed, use a laptop cooling pad or fan to keep temperatures in a safe range. Overheating can lead to failed backups and potential data loss.


In summary, it’s generally okay to use your computer while it’s backing up data to an external hard drive. However, best practices include avoiding taxing programs that utilize significant bandwidth, CPU, RAM, or graphics capabilities. Stick to light activities like web browsing, word processing, and simple media playback. Avoid gaming, video editing, batch photo processing, rendering, compiling code, or downloading large files if possible.

It’s also wise to pause syncing cloud storage services like Dropbox during backup to prevent bandwidth conflicts. Turning off antivirus scanning can also help maximize performance. Schedule long backup tasks during times you don’t need to use the computer, if feasible. Overall, moderate use during backups is fine, but heavy loads can slow the process and potentially corrupt data. Exercising caution allows you to multitask without significant downsides.