Convert Video to 120 FPS

120 FPS video can look remarkably fluid – but only on the right screen, and only with the right footage. This page explains when converting to 120 frames per second is worth it, what to expect from interpolated 120 FPS, and how to create it online with SmoothMotion.video. The tool above is already set to 120 FPS: upload a clip, start processing and download an MP4 when it is done.

Who 120 FPS is for

A higher frame rate only helps if your display can show it. A screen's refresh rate, measured in hertz (Hz), is the number of times per second it can draw a new picture. Here is how that interacts with video frame rate:

If you mainly watch on a 120 Hz phone, tablet, laptop or gaming monitor, 120 FPS can make motion look noticeably cleaner, especially on fast pans and scrolling. On a 60 Hz screen, choose 60 FPS instead – it processes faster and looks the same.

It is also worth checking where the video will end up. Many online platforms limit playback to 60 FPS and will convert higher rates down. 120 FPS is most useful for files you play locally, share directly, or use in an editing project.

How to convert a video to 120 FPS

1. Upload a video in MP4, MOV, MKV, AVI, WebM or M4V format, up to 500 MB, 5 minutes and 1920×1080.
2. Confirm 120 FPS is selected (it is pre-selected on this page).
3. Let it process. The file is checked to confirm it contains a valid video stream, then queued. While it is processed, you will see progress and a thumbnail refreshed periodically from the interpolated output.
4. Preview and download the MP4, named like clip_smoothmotion_120fps.mp4.

Original dimensions and audio are kept, and the playback speed does not change. The output is H.264 video with AAC audio in an MP4 container with faststart.

What happens when you interpolate to 120 FPS

For a 30 FPS source, the filter creates three new frames between every original pair. For a 60 FPS source, it creates one. For 24 FPS film, it creates an average of four per original frame. The more frames that are invented, the larger the proportion of the video that is synthesised rather than recorded:

This matters because every interpolated frame is an estimate. When motion is smooth and predictable – a slow pan, a drone fly-over, scrolling in a screen recording – those estimates are very convincing. When motion is fast, overlapping or chaotic, any artifacts are repeated across several consecutive frames and can become more noticeable. Interpolating from a 60 FPS source is the most reliable route to 120 FPS, because the gaps being filled are smaller.

Footage that suits 120 FPS

• High-frame-rate gameplay captured at 60 FPS that you want to view on a 120 Hz or 144 Hz monitor.
• Smooth camera movement: gimbal shots, drone footage, dolly and slider moves.
• Screen recordings and UI demos shown on high-refresh laptops and tablets, where scrolling looks especially crisp.
• Footage for an editing project where you want extra frames to work with, for example to slow a section down later in your editor.

Footage that is less suited includes 24 FPS film you want to keep looking cinematic, animation with held frames, and clips full of rapid cuts or erratic action. Read more about the trade-offs in 60 FPS vs 120 FPS.

Processing time and file size

Motion-compensated interpolation is CPU-heavy. At 120 FPS the filter renders twice as many frames as at 60 FPS, so processing takes considerably longer, and 1080p takes longer than lower resolutions. It is normal for processing to take longer than the duration of the video. Shorter clips are the best way to keep waits reasonable.

File size usually increases compared with a 60 FPS version, but not proportionally: consecutive interpolated frames are very similar to each other and H.264 compresses them efficiently.

Tips for better 120 FPS results

• Use the highest frame rate source you have. A 60 FPS recording interpolated to 120 FPS will generally look cleaner than a 30 FPS one.
• Use clean footage. Noise and heavy compression make motion estimation less accurate.
• Test a short section first if your clip contains lots of fast action.
• Watch on a high-refresh display to judge the result. Make sure your device's refresh rate is actually set to 120 Hz; some devices default to 60 Hz to save power.

How it is done

SmoothMotion.video uses motion-compensated interpolation with bidirectional motion search and overlapped block motion compensation, a well-established technique whose behaviour is predictable and consistent. If you want to know how each stage works, read our explainer on what motion interpolation is, or learn the basics of video frame interpolation.

Uploaded and processed media is deleted automatically 30 minutes after processing finishes, and no account is needed.