Frame rate
How to Convert 30fps Video to 60fps on iPhone (No Upload, No PC)
You ran a 30fps clip through a “60fps converter,” and the result looks exactly like the original. You didn’t do it wrong. Many converters change the frame rate number without changing the motion. This guide explains the difference, shows you how to check which kind of conversion you got, and walks through making a video truly 60fps on your iPhone, without uploading it anywhere.
THE SHORT ANSWER
- Yes, you can convert 30fps to 60fps on an iPhone. But it only looks smoother if the app generates a new frame between every pair of frames. That’s called frame interpolation.
- Many “60fps converters” duplicate frames instead. The file says 60fps, but the motion is identical. Play fast motion side by side and you’ll see it.
- In FrameFlo: pick the video, set Duration to Same Length, set Frame Rate to 60, and tap Add to Queue. Clips up to 10 seconds (or the first 10 seconds of a longer clip) can be converted and saved for free.
- It won’t help much if the clip is already 60fps, if it has heavy motion blur, or if it’s mostly fast cuts.
Can you convert 30fps to 60fps? Yes, but only one method looks smoother
A 30fps video holds 30 pictures per second. To turn it into 60fps, something has to fill the gap between every pair of frames. There are three ways to fill that gap, and only one of them changes what you actually see.
Duplicating frames: the file says 60fps, the motion doesn’t change
The simplest method shows every frame twice: 1, 1, 2, 2, 3, 3. The file now has 60 frames per second, so any app will report it as 60fps. But the picture still only changes 30 times a second, so motion looks exactly like the original.
Blending frames: smoother on paper, ghosting in practice
A step up is to make each extra frame a 50/50 mix of its two neighbors. Now there is something new between the frames, but anything that moves appears twice, half-transparent. On fast motion, that double image is easy to spot.
Frame interpolation: a new frame is generated
Interpolation looks at two neighboring frames and estimates how everything moved between them. Then it draws the picture for the moment halfway between. The image now really changes 60 times a second, so motion looks continuous instead of steppy. AI models such as RIFE have made this practical on a phone rather than only on a desktop GPU. For the full picture — methods, the soap opera effect and the downsides — see what frame interpolation is.
These three approaches are standard enough that the free tool ffmpeg offers exactly these modes in its motion interpolation filter: dup (duplicate), blend, and mci (motion-compensated interpolation) (ffmpeg documentation). So when an app promises to “convert your video to 60fps,” the real question is which of the three it does.
| Comparison | Duplicating | Blending frames | Interpolation |
|---|---|---|---|
| Fills the gap with | A copy of the previous frame | A mix of the two neighbors | A new frame drawn from estimated motion |
| Motion | Same as the original | Smoother, but moving things look doubled | Smoother; motion connects |
| File info says | 60fps | 60fps | 60fps |
| Processing | Little more than re-encoding | Light | Heavy: every new frame is computed |
| Usually found in | Export settings, many online converters | Some editors and converters | Dedicated apps and software |
Why your 60fps converter didn’t make the video smoother
If your converted clip looks identical to the original, the tool almost certainly duplicated frames. The frame rate number went up, and the motion stayed the same. This usually happens in one of three places:
- Export settings in a general video editor. Choosing “60fps” on an export screen sets the output frame rate. Unless the app says it generates new frames, assume the extra frames are repeats.
- Online converters. Many simply re-encode the file at the frame rate you pick. You also have to upload the video, wait for it, and stay under file-size limits, and the extra round of compression can cost some quality.
- Apps that pad frames to hit a number. Some apps exist mainly to make a file meet a frame rate spec. That’s a legitimate job, but it isn’t smoothing.
A useful hint: if a “60fps conversion” of a minute-long video finishes almost instantly, it probably didn’t interpolate anything. Generating frames takes real computation.
How to tell if a video is really 60fps
The frame rate shown in a file’s details can’t tell you which method was used. Your eyes can:
- Find a section with fast, steady motion, like a camera pan, a passing car, or a swinging arm.
- Play the original and the converted clip one after the other, at normal speed, on the same screen.
- If the converted clip stutters in exactly the same rhythm, the frames were duplicated. If moving edges look doubled or smeared, they were blended. If the motion looks clearly more continuous, it was interpolated.
If you also have a computer with ffmpeg, you can count repeated frames. Run ffmpeg -i converted.mp4 -vf mpdecimate -an -f null -. This filter drops frames that barely differ from the previous one. If the final frame= count is about half the clip’s total frames, half of them were duplicates. Use a section with constant motion, because frames from a still scene get dropped too.
How to convert a video to 60fps on iPhone with FrameFlo
FrameFlo is my app, so keep that in mind as you read this section. It runs the RIFE model on the iPhone itself and generates real in-between frames. The video never leaves your phone, and it works in airplane mode.
- Pick the videoOpen FrameFlo and choose a clip from your Photo Library or the Files app.
- Look at the Before columnThe Video Info screen shows the clip’s current frame rate, duration, file size, and output resolution. Next to it, an After column shows what you’ll get. This is free and requires no processing, so it’s also a quick way to check any video’s frame rate. Other ways to find a clip’s frame rate are in how to check a video’s frame rate on iPhone.
- Set Duration to Same LengthSame Length inserts generated frames and keeps the running time. (Slow Motion uses the new frames to stretch the clip instead.)
- Set Frame Rate to 60The choices are Same, 30, 60, and 120. Options at or below the source frame rate can’t be selected, so a 30fps clip offers 60 and 120, and a 24fps clip offers 30, 60, and 120. If you leave it on Same, no frames are generated, and the app warns you about this.
- Leave the other settings as they are (or adjust them with Pro)Inference Resolution is the image size the AI works at internally. Higher settings estimate fine detail better but use more time and memory, and they don’t change the size of the output. Export Quality sets the bitrate: Low, Medium, and High are 3, 8, and 20 Mbps. Output Resolution (No Change, or 480p to 4K) is a plain resize, not AI upscaling. On the free version these stay at Low, Low, and No Change.
- Check the estimate and tap Add to QueueThe After column updates as you change settings. That includes a processing load rating from Light to Very Heavy, which is the best guide to how long the job will take on your iPhone.
- Compare, then saveYou get a notification when it’s done. Drag the split slider to compare the original and the result on one screen, then save to your Photo Library or Files. The output is an MP4 file with HEVC (H.265) video.
Here’s what happens under the hood. Going from 30fps to 60fps, FrameFlo generates one new frame between each pair of original frames. The output is always exactly the frame rate you chose. When the numbers don’t divide evenly, as with 24fps to 60fps, it generates the in-between frames and then picks evenly spaced ones so the result lands exactly on 60fps.
For longer clips, turn on Keep Screen Awake While Processing (available in the free version too). On the free version, leaving the app interrupts the job. With Pro, processing continues for up to about 30 seconds after you switch apps. That’s the most time iOS gives an app in the background. If you stay away longer, the job starts over when you come back.
See the difference between duplicated and generated frames on your own 10-second clip.
Get FrameFlo on the App StoreFree to try · iPhone with iOS 16 or later
What you can do for free, and what needs Pro
Converting to 60fps at the same length is the part of FrameFlo you can fully use for free, including saving the result. The limits are clip length and output settings.
| Feature | Free version | Pro (one-time) |
|---|---|---|
| Clip length | Up to 10 seconds; longer clips: the first 10 seconds | Any length |
| Same Length frame rate | Up to 60fps | Up to 120fps |
| Save the 60fps result | Yes | Yes |
| Slow Motion (2× / 4×) | Create and preview (with a PREVIEW watermark) | Save |
| Export Quality | Low (3 Mbps) | Low, Medium, High |
| Inference Resolution | Low | Low, Medium, High |
| Output Resolution | No Change | No Change, 480p–4K |
| Queue | One video at a time | Up to 10 videos |
| Background processing | No (leaving the app interrupts) | Up to about 30 seconds after switching apps |
Pro is a one-time purchase, not a subscription. See the App Store for the price. If you change phones, use Restore Purchase with the same Apple ID.
Screen recordings and other variable-frame-rate clips
Not every video has evenly spaced frames. Screen recordings and some app exports use a variable frame rate: the gap between frames changes as the clip goes, so the “30fps” label is closer to an average. A converter that assumes every gap is the same can place new frames at the wrong moments, and motion can come out uneven.
FrameFlo uses each frame’s actual timestamp when it places the new frames, so variable-frame-rate clips are handled. One caveat: if a screen recording stutters because the recorder skipped frames, interpolation smooths the motion between the frames that exist. It can’t bring back what was never captured.
When converting to 60fps won’t help (or looks wrong)
- The clip is already 60fps. You can’t select 60, and there’s nothing to gain from it. The next step is 120fps (Pro), which only matters on a 120Hz screen or as editing material.
- It’s a “fake” 60fps file. A clip that was already converted by duplicating frames contains pairs of identical frames, so there is little motion to estimate between them. Start from the original if you still have it.
- Motion blur is baked in. If the subject is already smeared in each frame, the generated frames are smeared too. Interpolation adds frames, not sharpness.
- Scene cuts. Two unrelated shots have no real motion between them, so you may see one odd-looking frame right at the cut.
- Very fast motion or heavy shake. If something moves a long way between two frames, the model can lose track of it and warp the edges. FrameFlo has no stabilization, so shaky footage stays shaky.
- Thin lines, text, and overlapping objects. Hair, fences, nets, captions, objects passing in front of each other, water splashes, and see-through surfaces are the usual trouble spots.
- Very low frame rates. At around 10fps or less, the gaps are too big to fill convincingly.
Frame interpolation only changes motion. It doesn’t sharpen the image, remove noise, or fix compression artifacts. Output Resolution is a resize, so a small video exported at 4K doesn’t gain any detail.
If something looks off, use the split slider to check before you save. With Pro, try a higher Inference Resolution, or choose 60fps instead of 120fps. Processing a shorter section on its own also helps. Heavy settings can use more than 2GB of memory, so on iPhones with less memory (roughly iPhone 12 and older), iOS may close the app partway through. If that happens, lower the Inference Resolution, don’t push Output Resolution too high, trim the clip, and close other apps.
60fps or 120fps?
Going from 30fps to 120fps means generating three frames in every gap instead of one, so there are three times as many new frames to compute. Whether 120fps is worth it depends on your screen; the 120fps guide covers when it pays off.
In FrameFlo, 120fps is a Pro feature. It’s worth it when you’ll watch the video on a screen that refreshes at 120Hz, or when you plan to bring the clip into an editor and slow it down there. On a 60Hz screen you can’t see the difference between 60fps and 120fps. For social media, 60fps is the practical ceiling. See 30fps vs 60fps vs 120fps for what TikTok, Instagram, and YouTube document.
If what you actually want is slow motion, convert to slow motion directly rather than to 120fps. FrameFlo’s Slow Motion mode stretches the clip 2× or 4× while keeping the original frame rate. Our guide on making a normal video slow motion after recording covers that, including when the Photos app alone is enough.
FAQ
Can you convert 30fps to 60fps?
Yes. But to make it look smoother, the tool has to generate a new frame between each pair of frames (frame interpolation). Duplicating frames gives you a 60fps file that moves exactly like the 30fps original.
Is there a free 30fps to 60fps converter app for iPhone?
FrameFlo converts clips up to 10 seconds for free. For longer clips, it converts the first 10 seconds. You can save the 60fps result, at Low export quality. Converting full-length videos takes Pro, which is a one-time purchase. If you’re comparing other apps, our guide to choosing a frame interpolation app lists what to check in each free tier.
Does increasing fps increase video quality?
No. Higher fps makes motion smoother, but resolution, sharpness, and noise stay the same. Interpolation can’t add detail that wasn’t recorded.
How do I check a video’s frame rate on iPhone?
Choose the video in FrameFlo. The Video Info screen shows its frame rate in the Before column, free and without processing anything. Depending on your iOS version, the info panel in Photos (swipe up on the video) may also show it. There are more methods in this guide to the Photos app’s speed setting.
Why can’t I select 60fps in FrameFlo?
Your video is already 60fps or higher. Options at or below the source frame rate can’t be selected. You can choose 120fps (Pro) instead, or use Slow Motion if slow motion is your goal.
Is my video uploaded anywhere?
No. Processing happens entirely on the iPhone, and it works in airplane mode. The app only goes online for App Store price lookups, purchases, and restores.
How long does it take to convert a video to 60fps?
It depends on the clip’s length, the target frame rate, the Inference Resolution, and your iPhone model. The processing load rating on the Video Info screen gives you an estimate before you start. Try a short clip first to get a feel for it.
Written by punimaru, the developer of FrameFlo. App details are based on how the app is actually built. Since this is my own app, I’ve also noted where it isn’t the right tool and what else you can use.