What exporting does
Exporting, or rendering, turns your edit into a single video file that other people can play. Everything in your project, including clips, effects, titles, sound and color, is combined and then compressed. The settings you choose determine how sharp the picture looks, how large the file is and where it will play.
There is no single correct choice. The right export settings depend on where the video will be shown, how long it is and how much quality loss you can tolerate. The sections below cover the main decisions.
Know where the file is going
Start with the destination. A video uploaded to a large video platform, one embedded on your own website, one sent to a client and one kept as an archive each have different needs.
- Uploading to a platform. The service will usually re-encode your file anyway, creating several versions so that adaptive bitrate playback can suit different connections and screens. Your goal is to give it a clean, high-quality source within its accepted limits. Most platforms publish recommended settings, which are worth checking because they change over time.
- Hosting it yourself. You control the delivery, so you need a file that plays on most browsers and devices and loads quickly. Moderate settings and a widely supported format matter more here.
- Sending to a client or archiving. A higher-quality file is reasonable, since file size matters less.
If a platform re-encodes your video, uploading an extremely compressed file can make the final result noticeably worse, because it is compressed twice.
Resolution and aspect ratio
Video resolution is the number of pixels in the frame, such as 1920 by 1080 or 3840 by 2160. A good default is to export at the same resolution as your project. Scaling up from a lower-resolution source does not add real detail, and scaling down is fine if you need a smaller file.
Match the shape of your project too, since aspect ratios differ widely between platforms. Exporting a vertical project into a widescreen frame, or the other way round, usually adds black bars or crops the picture. Choose the shape that suits the platform where viewers will watch.
Frame rate
Export at the frame rate you edited in, unless you have a reason to change. Converting, for example, from 24 to 30 frames per second can cause uneven motion because frames must be repeated or blended. Common frame rates include 24, 25, 30, 50 and 60 frames per second, and the right one often depends on how the footage was shot and the viewing platform.
Format, container and codec
Two terms are often mixed up. A codec is the method used to compress the video and audio. A container is the file type that holds them together, such as MP4, and the differences between container formats affect what can be stored inside.
For web delivery, a very common combination is an MP4 container with video compressed using the H.264 codec and audio compressed with AAC. It plays on a wide range of browsers, phones and televisions. Newer options can deliver the same quality at smaller sizes but may not be supported everywhere, which can matter if you host the file yourself.
If you are unsure, an H.264 MP4 is the safest general-purpose choice. Remember that these codecs use lossy compression, which discards some information to reduce size, so each re-encode can lower quality slightly.
Bitrate: the quality and size dial
Video bitrate is the amount of data used per second of video. A higher bitrate usually means better quality and a bigger file, up to a point of diminishing returns. The right figure depends on resolution, frame rate, the codec and how complex the footage is. Fast motion, grain and detailed textures need more data than a still, simple scene.
You can estimate file size from bitrate with simple arithmetic. File size is bitrate multiplied by duration. For example, a video stream at 10 megabits per second lasting 60 seconds uses 10 x 60 = 600 megabits. Dividing by 8 gives 75 megabytes. Audio and container overhead add a little more. This is only an estimate, but it helps you see how bitrate and length drive file size.
Many export dialogs offer two main modes:
- Constant bitrate (CBR). Uses the same amount of data throughout. Predictable, but it can waste data on simple scenes and starve complex ones.
- Variable bitrate (VBR). Gives more data to complex scenes and less to simple ones, usually producing better quality for a given file size. Two-pass VBR analyzes the video first and then encodes it, which is slower but often more efficient.
For uploads to platforms and for most web video, variable bitrate is a common choice. Constant bitrate is more often required for live streaming and some broadcast workflows.
If your editor offers a quality-based setting rather than a bitrate, that is often a good option for a one-off file, because it adapts to the footage. Always check the result rather than trusting the number.
Audio settings
Audio is a small part of the file but important. A common choice for web video is AAC audio, stereo, at a sample rate of 48 kHz. A bitrate in the range of roughly 128 to 320 kbps is often used, with higher figures for music-heavy material. Make sure the loudness and peaks are checked during mixing, because an export cannot fix a problem baked into the mix.
Hardware or software encoding
Some editors let you choose between using your computer’s graphics hardware or the processor to encode. Hardware encoding is usually faster, while software encoding often gives somewhat better quality at the same file size, though results vary between machines and programs. If quality is the priority, try both on a short test.
Other settings worth knowing
- Color. Standard dynamic range video using common web color settings is the safest option for most uses. Special color or HDR exports need compatible playback to look right.
- Fast start. For files on a website, some encoders can place the information needed to begin playback at the start of the file, so the video can start before the full file has downloaded.
- Metadata and captions. Some formats can carry titles and chapters, and captions may be embedded or uploaded separately.
Test before you publish
- Export a short section, such as 20 to 30 seconds with a mix of fast and slow scenes.
- Watch it on a different device from the one you edited on.
- Check sound, sync between picture and audio, text legibility and any banding in gradients or blockiness in dark scenes.
- Adjust and repeat, then export the whole thing.
Keep a high-quality master file of the finished edit, alongside your project, so you can create other versions later without starting from a compressed copy.
A web version is always a compromise between quality, speed and compatibility. Starting from common, widely supported settings, then adjusting one thing at a time, is a reliable way to find a setup that suits your work.