B-Roll to A-Roll Ratio Checker for Video Edits

This B-roll to A-roll ratio checker turns the total duration of primary footage and supplementary footage into a clear percentage, then compares that percentage with a practical guidance range for the selected content type. It gives editors, producers, and reviewers a consistent starting point for discussing pacing without pretending that one ratio can replace editorial judgment.

Measure the footage that appears in the finished edit

Start with the total screen time occupied by primary A-roll and supplementary B-roll in the current cut. A-roll usually means the interview, presenter, conversation, or principal action that carries the narrative. B-roll means the supporting images placed over or around that primary material: demonstrations, locations, details, archive shots, product views, cutaways, graphics treated as footage, or other visual evidence. Enter both totals in seconds, using the same timeline boundaries and counting only material that actually appears in the edit. Do not use the duration of every source clip in a bin, because unused takes would inflate the result. The checker adds the two durations and divides B-roll by that combined total. For example, 180 seconds of B-roll within a 600-second measured edit equals 30 percent. Overlaps need a consistent rule: if an inset or split screen shows A-roll and B-roll simultaneously, choose the dominant visual category and count that interval once. This prevents double counting and keeps comparisons between successive cuts meaningful.

Read the guidance as a pacing signal, not a creative law

The result is compared with a broad range selected for the content type. Interviews often preserve more face time and therefore use a lower B-roll range, while tutorials, documentaries, and short social videos commonly need more visual changes, demonstrations, context, or pattern interruption. A result within the range means the measured balance resembles that common pacing pattern. A result below guidance suggests that the edit may rely heavily on the primary shot; look for claims that need visual proof, pauses that need coverage, transitions that feel abrupt, or stretches where attention drops. A result above guidance suggests that supplementary visuals may be displacing the speaker, lesson, or central action. Neither status proves that an edit is wrong. A compelling performance can sustain long A-roll passages, and a visual essay may appropriately exceed a documentary range. Use the difference in percentage points to size the deviation, then watch the edit at normal speed before changing it. Rhythm, shot relevance, emotional continuity, accessibility, and audience expectations remain more important than hitting a target mechanically.

Use the ratio during review and revision

Record the calculation for each meaningful cut rather than treating it as a one-time score. Early assemblies often contain long A-roll sections because supporting footage has not been placed yet. A later cut may swing too far in the other direction when every sentence receives a literal illustration. Comparing the percentage across versions helps a team see what changed and gives reviewers precise language: instead of asking for vaguely more energy, they can identify a twelve-point shortfall against the selected pacing band and discuss where additional visuals would clarify the story. Segment-level checks are useful too. A ten-minute program can have a balanced total while one chapter contains no visual relief and another is overloaded with rapid cutaways. Run the same calculation for chapters, speakers, or scenes when local pacing matters. Keep the content type stable when comparing versions, and document any deliberate exception. The API price is $0.002 per request, making the same deterministic calculation suitable for edit reports, quality-control checklists, and automated review dashboards as well as individual browser checks.