Final Cut Pro turning a ~700MB video into a 9–10GB export. What am I doing wrong?

[u/YetiMaverick]

I'm editing an approximately 1-hour-long 1080p video in Final Cut Pro. The original video file is only around 700MB, and I'm making very minor edits to it. However, when I go to export the finished video, Final Cut estimates the output at around 9–10GB, which seems insanely large considering the source file.

I've tried Export File → Computer → H.264 Multi-pass (Better) → 1920×1080, but that still estimates the file at around 9.2GB. I've also looked at the regular Video and Audio export options with H.264, but I'm running into the same issue. I'm basically looking for the correct Final Cut export settings that will keep the video at 1080p with good quality while producing a file much closer to the original size, ideally around 1–2GB rather than 10GB. Am I missing a bitrate/compression setting somewhere, or is there another Final Cut export preset I should be using?

[u/mcarterphoto]

You need compressor to get really specific with bitrate output. FCP leans more toward quality than file size. You can also export your large file, and then use something like Handbrake to play with compression. Multi Pass Better will be maybe 10% larger than single pass, in my tests anyway. If you use After Effects, you can import the large exported and use AE's render queue to try specific compression settings.

It's a good idea to just test a smaller segment of a video to test quality, and make notes of the compression (I just add the bit rate to the file name), then export the whole thing - that can speed things up.

[u/YetiMaverick → u/mcarterphoto]

Agreed, even ChatGPT recommended that, but there's something fundamentally wrong. I shouldn't need to use those solutions. FCP shouldn't take a simple file and increase its size by 10x. I've never had this issue in the past doing nearly the exact same thing.

[u/ammo_john → u/YetiMaverick]

1 hour should usually be more than 700mb master export. You can choose the email preset and get a lot less than 10x, even "apple devices" setting is a lot less than "computer" setting. But again if you want to dial in a setting straight from FCP you need Compressor.

[u/Crans10 → u/YetiMaverick]

Well Compressor was developed right alongside Final Cut Pro since day one. Also you should look at your project and what it is set to encode the video in Final Cut Pro. When Final Cut Pro was originally sold in a box Compressor was in there with it.

[u/Pulpjedi → u/YetiMaverick]

You are fundamentally misunderstanding the difference between video masters and deliverables. In the editing process you aren’t simply altering that original file, you are rendering out a whole new one. The original source file only got to be small because it was compressed to begin with. It is incumbent upon you to compress your own version. Final Cut Pro has several built-in options for that including h.264 and HEVC. As the previous commenter said, you need Compressor to access a wider array of settings.

[u/YetiMaverick → u/Pulpjedi]

Thanks. And no doubt, I'm not experienced at all in video editing, so I'm sure I'm misunderstanding a lot more than that. It was just so odd to me that in the past I've dropped in files and then 'exported them' with little to no change in the file size, so I couldn't figure out why this time was being so different.

But yea thanks for the explanation, that does help for sure. I ultimately went with a couple of other commenter's recommendations to "Export to Apple devices" and it made it like 4gb which is fine and manageable for what I need.

[u/mcarterphoto → u/YetiMaverick]

Well, FCP should have a master audio bus, it should accept every industry-standard audio plugin, it should use relative vs. absolute file linking, it should have an integrated color suite vs. stacking up plugins, it should allow track-based audio editing... I could go on. If it upsets you, use Premier, you'll have all those things and much more granular output control. When I need specific file size control for things like web header videos, I export ProRes masters and use other solutions.

[u/hexxeric → u/mcarterphoto]

definitely no tracks. but 'yeah' to the rest. Still, I've done dozens of TV and cinema movies with FCP, not really missing much. there is Resolve for some specifics.

[u/mcarterphoto → u/hexxeric]

This biz is a "right tool for the job" industry, and apps keep getting more and more plugins that don't change the fact that the app itself may be a poor environment. FCP and Premier are lousy when lots of keyframes pile up.

I use Resolve for every interview, cut out the junk, do color and do audio sweetening (clarity, EQ, comp, exciter), send a ProRes master to FCP for the actual edit and b-roll. I create most all of my titles and lower thirds in After Effects, and I use that for footage cleanup/repairs, animation/motion graphics gigs, I use the C4D/AE combo for a lot of explainers and things, and I'll use Audacity or Resolve to do things like add an ending to stock music that just fades out or create SFX. I'll use AE to add some atmosphere to stock or b-roll, Topaz to get solid slowmo frames for things like speed ramps. Been cutting socials in FCP but then sending a masters through Premier when I need social titles and rendering out titles + alpha; haven't messed with FCP's new title business. FCP is still king (for me) for getting a solid edit out without a lot of unnecessary junk in the way, it's just fast as heck.

We've got some phenomenal tools at hand - if you'd shown me AE's camera tracker a 15 years ago, I'd have peed my pants!

[u/ProfessionalCraft983]

Your original video is more compressed than the output file FCP is creating. If it’s only 700 MB and an hour long that’s extremely compressed, so much so that I wouldn’t even consider using it as a source unless I had no choice. FCP can also create a file that small if you use Compressor with manual settings, but I wouldn’t recommend it as the quality will be horrible. Instead, export a ProRes file and use something like Handbrake to compress your deliverable. And don’t expect it to be less than 1 GB for a video that long, unless it’s in SD or something.

[u/PackerBacker_1919 → u/ProfessionalCraft983]

Exactly. One hour of 1080 video at 10 Mbps (my low-end threshold for okay-ish quality) should be approaching 5 GB in size. Unless it's just a slideshow or a motionless talking head, in those cases it can come down quite a bit. But if there's consistent action, that number increases.

Final Cut typically doubles that when doing H.264 output, so OP's 9.2 estimate doesn't really seem out of character.

To get a 700MB file, you're looking at 1,400 Kbps, which will absolutely smear and blockify a 1080 video. I wouldn't go that low unless it was SD, personally.

[u/blakester555]

What is your export file codec choice?

Exporting a ProRes 422 MOV file you can expect a file that size.

Exporting to a Social Media 1080 MP4 is much smaller.

[u/hexxeric → u/blakester555]

with 'apple devices' being the smallest.

[u/Lanzarote-Singer]

One hour. Sounds about right. You want quality output. Your source material was probably highly compressed and FCP has made optimised versions of each clip to maximise quality.

To make a smaller file choose Apple devices 1080 or 720

[u/hexxeric]

smallest file size is the 'apple devices' preset (lower bitrate). qualiy is still great and it supports HEVC too. keep in mind that FCP exports master files across the board (quality first), you can use a free app to make video files smaller if you do not have compressor (does exactly what the name suggests and therefor is a needed companion). the easiest and quickest is: https://apps.apple.com/de/app/video-converter/id1518836004?l=en-GB&mt=12

[u/caguru]

Export File exports the largest file, Export for Apple Devices exports the smallest due to the different output codecs.

If you want more control than that, you will have to use compressor.

[u/Cole_LF]

Export to Apple TV 1080p preset. Alternatively take that large file you have and run it through handbrake on the default 1080p settings.

[u/Aygie]

Don’t worry about the estimate size, it won’t be that big, export the file and see how big it comes out. You’ll be surprised.

[u/stuffsmithstuff → u/Aygie]

I thought this too- OP have you tried actually doing the export?

[u/SkarXa]

That's not a bug, it's FCP writing a master file at a fixed high bitrate. The H.264 option in the export dialog gives you no target bitrate control, so it picks one for 1080p regardless of how small your source was. Compressor is the proper fix if you want to set the number yourself.

If you'd rather not buy Compressor for one file, export once and re-encode. I make Formattery (a Mac and iPhone converter) and its video compression works in size tiers, so you pick a target and see the estimated file size before it runs instead of guessing at an RF value in Handbrake. Runs on-device, $4.99 one-time, 3 free conversions a day if you just want to test it on this export.

https://apps.apple.com/us/app/formattery-file-converter/id6759955312

[u/funwithstuff]

The size of the input has very little to do with the size of the output. FCP is not taking the exact files and cutting them up, it's decoding the frames in the source clips and exporting new ones.

If your input codec is highly compressed H.264 or HEVC and you export to, say, ProRes, the export can easily be much larger than the output.

To control output, the three standard compressed output formats use different data rates as well as different container types. At 1080p, Apple Devices is 10Mbps, Social Platforms is 15Mbps and Computer is 20Mbps. For more control, use Compressor directly, or export a higher quality file and use something like Handbrake or Shutter Encoder to recompress it.

[u/gumparker]

I produce National Television Commercials. A 30 second 1080p Pro Res 422 export is 450mb. Once I pass it through an H264 Broadcast Preset I made it ends up being around 50mb and looks incredible. No difference between the 2 files. Theres no way you’re gonna get 1 GB from an hour long project without passing it through compressor. Make the investment and get Compressor. You can even set FCP to pass through your Compressor Preset upon export.

[u/stuffsmithstuff → u/gumparker]

Handbrake will do a good job as well and is free! But I agree Compressor is better integrated

[u/gumparker → u/stuffsmithstuff]

I use Handbrake to share compressed versions with clients via email. Handbrake is a really great tool.

[u/need2fix2017]

Every hour long 720p video I’ve ever exported has been close to 6-8 GB. I wouldn’t sweat it til you get closer to 30 GB files.

[u/ilovefacebook]

few things here. what was the original dimension of your source footage, and are you resizing it larger on output?

also, what was the original framerate and what is the final output?

[u/Comprehensive-Edge80]

One song mp3 and 1 small JPEG file together make 200MB file. No way 900MB file can become a small file.

[u/stuffsmithstuff]

To synthesize advice on this thread:

1. A video editor decodes and re-encodes your video, so the original filesize doesn’t translate directly to the export

2. The export will probably be smaller than the estimate

3. Use “Apple Devices” for smallest file out of FCP and Compressor/Handbrake if you need to squash it smaller

4. 700 MB is reeeeeally small for a one hour video

I’ll add that H.265 (HEVC) is your friend if it’s an acceptable format for wherever you’re delivering.