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Step 1: Lower the playback quality in the Program Monitor
The fastest fix is in the Program Monitor. Click the wrench icon to open its settings menu and look at High Quality Playback. If it has a tick, turn it off so Premiere does not try to show every frame at the highest quality while you edit.
Next, open the Select Playback Resolution drop-down, which says Full by default, and pick a lower value such as 1/2, 1/4 or 1/8. The video uses 1/4 and then 1/8 for heavy footage. The preview looks softer while you edit, but your export is not affected, since exports always use the full resolution.
Step 2: Render the heavy part of your timeline
A red line above the timeline means Premiere struggles to play that section in real time. Set an In and Out point around it, then go to Sequence > Render In to Out. The shortcut for Render Effects In to Out is Enter, and the render dialog shows its progress.
When the render finishes, the red line turns green and that section plays smoothly. The preview files are only for playback, so if you edit the clip again you may need to re-render it.
Step 3: Give Premiere more RAM
Premiere only uses the memory it is allowed to use. Go to Edit > Preferences > Memory (on a Mac, Premiere Pro > Settings > Memory). Under RAM reserved for other applications, lower the value so more memory is available for Premiere. In the video, the computer has 16 GB installed and the reserved amount goes down to 3 GB, which leaves 13 GB for Premiere.
Do not set it too low. Your operating system and any other apps you keep open still need some memory. Restart Premiere after changing it.
Step 4: Clean the media cache
Premiere stores helper files such as audio waveforms and conformed audio in its media cache. Old files can slow things down. Open Preferences > Media Cache, click Delete next to Remove Media Cache Files, choose Delete unused media cache files and click OK.
Under Media Cache Management, you can also tick Automatically delete cache files older than and set a number of days. The video has it set to 7 days, so Premiere cleans up after itself.
Step 5: Use accelerated effects and Global FX Mute
Some effects are much heavier than others. In the Effects panel, click the Accelerated Effects button next to the search box to show only effects that use your graphics card. Picking from that list keeps playback smoother than using effects that run on the CPU alone.
You can also switch all effects off while you edit. Click the + in the Program Monitor to open the Button Editor, drag the Global FX Mute button (the fx icon) onto the toolbar and click OK. One click on the new button turns every effect off for smooth playback, and another click brings them back.
Step 6: Create proxies for heavy footage
If the footage itself is the problem, such as 4K or high-bitrate clips, proxies are the best fix. Right-click the clip in the Project panel and choose Proxy > Create Proxies. In the dialog, keep QuickTime as the format and pick a preset such as ProRes Low Resolution Proxy. Choose where to save them, for example Next to Original Media, in Proxy folder, and click OK.
Adobe Media Encoder opens and creates the small, easy-to-play copies in the background. Add the Toggle Proxies button to the Program Monitor with the Button Editor, and click it to switch between proxies for editing and the original files. Premiere still exports from the original footage.
Tips
- Start with the easy fixes. Lowering playback resolution and turning off High Quality Playback cost nothing and often solve the problem alone.
- Keep your drives tidy. Cache and preview files need free space, and a nearly full drive slows everything down.
- Switch things back before export. Make sure Global FX Mute is off and proxies are toggled off, or your export may be missing effects.
FAQ
Does lowering the playback resolution reduce my export quality?
No. Playback resolution only changes how the preview looks while you edit. The export uses your sequence and export settings.
Why is there a red line above my timeline?
Red means that section is too heavy to play in real time. Render it with Sequence > Render In to Out and the line turns green.
How much RAM should I leave for other applications?
It depends on what else you keep open. The video lowers it to 3 GB on a 16 GB system, but if your computer becomes sluggish, raise it a little again.
Once your playback runs smoothly, speed up the rest of your editing too. BetterFX lets you apply effects from the keyboard without searching the Effects panel.
