OBS takes between 500 MB and 2 GB of disk space to install, but the real storage question is how much room your recordings will need

Open Broadcaster Software (OBS) itself is a small program. The installation file is roughly 500 MB, and once installed on your drive, OBS occupies about 1 to 2 GB depending on your operating system and which plugins you add. That is not the storage problem most people face.

The actual drain on your hard drive comes from video files. A single hour of video recording at standard quality settings can consume 5 to 15 GB of space. At high quality, that same hour can reach 20 to 50 GB. If you record regularly, those files add up fast, and you will need a plan for where they live and how long you keep them.

Key Takeaways

  • OBS software itself uses 1 to 2 GB of disk space once installed, which is negligible for most modern drives.
  • Video file size depends on your resolution, frame rate, and bitrate settings — a one-hour recording at 1080p 60fps can range from 5 GB to 30 GB.
  • Recording directly to an external hard drive or secondary internal drive is faster and safer than recording to your main system drive.
  • You should reserve at least 10 to 20 percent of your total drive capacity as free space to keep your system running smoothly while recording.

How Recording Settings Control File Size

The size of your video files depends on three settings you control in OBS: resolution, frame rate, and bitrate. Resolution is how many pixels wide and tall your video is — 1080p (1920 × 1080) is standard, but 720p is smaller and 1440p or 4K are larger. Frame rate is how many individual images per second the video contains — 30 fps is common, 60 fps is smoother but creates bigger files. Bitrate is how much data the video encoder writes per second, measured in kilobits per second (kbps).

A rough example: recording at 1080p, 30 fps, and 6000 kbps bitrate produces roughly 2.7 GB per hour. The same resolution at 60 fps and 10000 kbps produces roughly 4.5 GB per hour. If you drop to 720p at 30 fps and 4000 kbps, you get closer to 1.8 GB per hour. The math is straightforward — higher numbers in any of these three settings mean larger files.

Your internet upload speed, if you are streaming, does not directly control file size. Streaming bitrate and recording bitrate are separate settings in OBS. You can stream at a lower bitrate to your platform while recording locally at a much higher bitrate, which is why local recordings are often higher quality than what viewers see.

Where to Store Recordings to Avoid Slowing Your System

OBS lets you choose where to save video files. The default location is usually your Documents folder or Desktop, both of which sit on your main system drive. Recording directly to your main drive while your operating system is also running programs, updating files, and managing memory can slow everything down. The system drive has to juggle recording data, system processes, and user programs all at once.

A better approach is to record to a secondary drive — either a second internal hard drive, an external USB drive, or a network drive. External USB 3.0 or 3.1 drives are fast enough for most recording scenarios. If you use an external drive, plug it in before you start recording and leave it connected until the file finishes writing. Unplugging during recording can corrupt the file.

If you only have one drive, record to a folder on that drive but monitor your free space carefully. Windows and macOS both need 10 to 20 percent of your total drive capacity to remain free for system operations. If your drive fills past 80 percent capacity, your system will slow down noticeably, and recording may stutter or drop frames.

Calculating Storage Needs for Regular Recording

If you record several times a week, storage planning matters. A streamer who records 20 hours per week at 1080p 60fps and 8000 kbps bitrate will generate roughly 36 GB per week, or about 150 GB per month. That same person recording at 720p 30fps and 4000 kbps would generate roughly 9 GB per week, or about 36 GB per month.

Most people keep recent recordings and delete older ones. A common strategy is to keep the last two to four weeks of recordings on fast local storage, then move older files to external backup drives or cloud storage if you need them for reference. This keeps your active recording drive from filling up while preserving important files.

Before you start recording regularly, check how much free space you actually have. On Windows, right-click your drive in File Explorer and select Properties. On macOS, click the Apple menu, select About This Mac, then Storage. Subtract 20 percent of your total capacity as a safety buffer, then divide what remains by the file size per hour at your planned settings. That tells you how many hours you can record before you need to delete or move files.

Codec Choice and File Format Impact

OBS offers different codecs — the algorithms that compress video data. The most common are H.264 (also called AVC) and HEVC (also called H.265). H.264 is older, more widely compatible, and produces larger files. HEVC is newer, produces smaller files at the same quality, but not all devices or platforms support it. If you are streaming to Twitch, YouTube, or another platform, check whether they support HEVC before you choose it for recording.

The file format (the container) also matters slightly. OBS defaults to MP4 for most users, which is widely compatible. MKV (Matroska) is another option that handles some edge cases better, but fewer devices play MKV files natively. For most purposes, MP4 is the safer choice unless you have a specific reason to use something else.

Managing Storage When You Record Frequently

If recording is part of your regular workflow, treat storage like you would treat any other system resource. Set up a dedicated external drive for recordings and keep it plugged in during sessions. Once a week or once a month, depending on how much you record, move files you want to keep to a backup drive or cloud storage, then delete the working copies from your recording drive.

Many people use a tiered system: fast local SSD for active recordings (last week or two), external USB drive for medium-term storage (last month or two), and cloud or archive storage for files they might need later. This keeps your recording drive fast and responsive while preserving important files.

If you are unsure what bitrate to use, start with the OBS defaults for your resolution and frame rate, then record a short test clip and check the file size. OBS displays the file size in the file properties once recording stops. That real-world number is more useful than any estimate, because it accounts for the actual content you are recording — some scenes compress better than others.

Frequently Asked Questions

Does OBS use storage space while I am not recording?

No. OBS uses a small amount of RAM while the program is open, but it does not write to your hard drive unless you are actively recording. Once you close OBS, it stops using system resources. The only permanent storage OBS takes is the 1 to 2 GB for the program itself.

Can I record to a USB flash drive instead of an external hard drive?

You can, but it is not ideal. USB flash drives are slower than external hard drives, especially for sustained writing. Recording at high bitrates may cause dropped frames or stuttering. External USB 3.0 or 3.1 hard drives are much more reliable for recording.

What happens if my drive fills up while I am recording?

OBS will stop writing to the file, and your recording will end prematurely. The file may be corrupted or unplayable. Always monitor your free space before you start recording, and keep at least 10 to 20 percent of your drive free.

Does streaming to Twitch or YouTube use the same storage as local recording?

No. Streaming sends data to the platform's servers in real time but does not save a copy on your computer unless you also enable local recording. You can stream without recording, record without streaming, or do both at the same time with separate bitrate settings for each.

Should I use an SSD or a regular hard drive for recording?

Either works, but SSDs are faster and more reliable for sustained recording. If you are recording at very high bitrates (above 20000 kbps), an SSD is safer. For standard recording at 1080p or 720p, a regular external hard drive is fine and costs less.