Use Same as Source with Variable Framerate (VFR) when you want to keep the source’s timing and your destination accepts it. Use Peak Framerate (PFR) when you need a ceiling. Use Constant Framerate (CFR) when your editor or delivery specification requires one fixed rate. The number in the frame-rate selector and the mode beside it work together; check both before starting a long encode.
This guide concerns readable Blu-ray backups and home videos you own or are authorized to process. Keep the source as your archive and make a separate playback or editing copy. If you still need to choose an output format or tool, start with the Blu-ray-to-MP4 decision guide.
Choose the timing goal first
| Your actual requirement | Setting to consider | What to check before using it |
|---|---|---|
| Keep the source’s timing; no fixed-rate requirement | Same as Source + VFR | The destination must accept the resulting stream and its other video/audio settings. |
| Stay below a documented maximum, without forcing slower material up to that rate | A numeric rate + PFR | A ceiling is not a promise of CFR. Use CFR instead if the specification demands it. |
| Deliver a constant rate to an editor or another destination that explicitly requires it | CFR + the exact required rate | Conforming timing can change the original cadence. Check moving scenes and the finished file. |
| You do not know what the source or destination requires | Inspect both before choosing | A Blu-ray, MKV or MP4 label alone does not answer the frame-rate question. |
Frame rate is measured in frames per second (fps). It is a separate choice from the quality or bitrate setting. Selecting CFR does not select constant bitrate; selecting VFR does not select Constant Quality. Use the Constant Quality vs Average Bitrate guide for picture-quality and file-size decisions.
Same as Source does not tell the whole story
HandBrake’s frame-rate documentation distinguishes the selected rate from its control mode. With Same as Source + VFR, HandBrake follows the source timing instead of imposing a new rate. The VFR option allows variable timing; it does not require a constant-rate source to become variable.
Same as Source + CFR is different: it still makes the output constant. The current CLI reference describes CFR without a specified rate as using the source’s average rate. Therefore, “same” is not a promise to preserve every timestamp when CFR is enabled. If the receiving workflow specifies an exact rate, choose that rate explicitly.
Neither setting says the picture is lossless or that HandBrake is merely changing the container. HandBrake always converts the video. Treat the result as a new encoded copy and retain your original.
PFR is a ceiling, not an instruction to speed everything up
Consider two hypothetical progressive sources, with no filters changing their cadence:
- A 23.976 fps source with a 30 fps PFR limit is below the ceiling. That limit does not require it to become 30 fps.
- A 60 fps source with the same 30 fps PFR limit exceeds the ceiling. The output is limited to 30 fps; it cannot retain the source’s full 60 fps cadence.
These are illustrations of the documented rule, not results from an encoding test. Check that a limit is necessary before reducing a source’s rate.
The current official presets guide describes the numbers in General preset names as maximum resolution and frame rate. A name ending in 1080p30 should not be read as “every source becomes constant 30 fps.” It also documents Production presets as CFR. Inspect the selected preset’s settings instead of assuming every preset uses the same mode.
Use CFR for a specific requirement
Write down the receiving editor’s or service’s actual requirement before overriding the source. Keep 23.976 and 24, or 29.97 and 30, distinct when the requirement names one of them. Do not round a value simply because the shorter number looks familiar.
If a source mixes rates, CFR must conform that timing to one rate. A successful encode alone does not tell you whether its motion is acceptable in the intended use. Watch pans, fast movement and transitions in the receiving application.
Interlaced or telecined material needs a separate source-and-filter decision. The CLI documentation notes that detelecine and a forced CFR setting can interact. Do not use “all Blu-ray should be 24 fps” as a shortcut, or force a rate while leaving an unrelated combing or cadence problem unexplained.
Likewise, changing to CFR is not evidence that an audio-sync problem is solved. Compare the original and output in the same relevant section, then check the copy in its actual destination. If the symptom remains, retain the sample and settings for diagnosis rather than processing the whole library.
Check one copy before queuing the library
- Record the starting point. Note the source title, duration and reported frame-rate information, plus the destination’s requirement. Keep the source file intact.
- Record both controls. Save the selected rate and VFR/PFR/CFR mode along with the preset, encoder and any filters. This makes a changed result easier to explain.
- Make a representative sample. HandBrake’s Preview function can encode a selected short section. Choose movement and, where available, dialogue; inspect it in the intended player or editor.
- Check the complete output. Confirm that the reported rate/mode meets the requirement. Compare duration, motion and audio alignment near the beginning, middle and end; check retained tracks as well. A good short preview cannot validate every part of a long file.
- Keep the archive and the decision record. Follow the backup verification checklist before treating the new file as a usable copy. A readable header or matching copied-file hash does not establish playback compatibility.
Sources and limits
Official sources were checked on 28 October 2026. The Frame rate page explicitly identifies itself as a draft; its mode definitions were cross-checked against the current CLI reference. Its broad statement about all built-in presets is not used here because the current presets page separately describes Production CFR behavior.
This is a documentation-based settings guide. We did not perform a HandBrake encode or test a physical Blu-ray, optical drive, player or editing application for this article. The choice table helps you plan a test; it does not certify your source or destination.