How to Batch Compress Videos to Smaller Size (PC & Easy)

Launch WonderFox HD Video Converter Factory Pro and enter the "Converter" program.

Next, click the center + button or the upper-left "+ Add Files" to import your videos into the program. Alternatively, you can drag the source files directly into the interface.

Open the right-side output format list and go to the "Video" category. Select your preferred output profile from the options below.

💡 Tip: When you choose a different format than the original video, it may immediately affect the output size because it may be compressed with a different codec. You can jump to #More Tips to learn about the most efficient codec that may significantly reduce your video size while maintaining quality.

Click the Compression button on the main interface and drag the slider to the right to set the compression ratio until you get the desired size. You can see the output size change in real time while dragging the slider.

💡 Tip: With this software, you can achieve extremely small size by setting the highest compression rate. But the resulting quality will be very poor. So if you want to get a decent output video quality, remember not to set the compression rate too high, or try other compression tips below.

At the bottom of the workspace, click the ▼ button to set an output folder in advance. Make sure it has ample free space.

Finally, click the "Run" button to compress multiple videos at once.

Besides utilizing the compression button, if you want to have more control over the output quality instead of focusing purely on size, here are more tips to help you with it.

🔍 You may click the ⓘ icon to know details of your video parameters like codec, bitrate, frame rate, etc. before proceeding.

Use advanced video encoder is most recommended. While in step 2, you can choose the H265 profile ("H265 for MP4" or "H265 for MKV"). This profile uses the H265/HEVC codec can re-encode your video (if your video is encoded with a different codec) to a much smaller size file without sacrificing the video quality. Notably, an H264 video can be reduced to half size when being re-encoded using H265, and older codecs such as MPEG-2, MPEG-4, and VP8 can be re-encoded with even higher compression rates.

Adjust video settings according to specific needs. You can also manually adjust the video settings to reduce file size and suit specific needs. Just go to "Parameter settings" and change the encoder (codec), resolution, and bitrate as you see fit. These parameters are what affect the quality the most.

I’ve explained a bit about codec before and you can use H265 as the video encoder (provided that you select MKV or MP4 as the output format). Then you can set the resolution to a lower value if you’re okay with a bit of quality drop. For example, if the original video is 4K quality, you can set it to 1080p, which can greatly shrink the file size.

Bitrate is the tricky part. I suggest you let the program smart-fit the bitrate based on the settings you’ve made already to balance the quality and size. But if you’re confident with the bitrate you want to use, customize it the way you like.

* You can experiment with different settings to know what’s best for your case.