Reconcile documented source frames, exact rational source and target rates, same-duration target slots, and same-frame-count interpreted duration without selecting a conversion method.
A quick decision brief for this specific tool
One de-identified frame-rate record; named reviewed source frame-count, source-rate, source-duration, target-rate and two independent comparison records; positive whole rational-rate numerators/denominators and source frame count; positive source duration; and nonnegative independent target-slot and interpreted-duration values
Source-preserving record basis, exact rational source/target rates, reproduced source duration and signed difference, same-duration target slot-equivalent and signed independent difference, plus same-frame-count interpreted duration, signed difference and speed/duration ratios
Divide exact rate numerators by denominators, divide the reviewed whole source-frame count by source fps to reconcile source duration, multiply documented source seconds by target fps for a same-duration slot-equivalent, and divide the same source-frame count by target fps for interpreted duration; do not choose cadence, sampling, duplicate/drop, blending, interpolation, optical flow, conform, retime, timecode, audio or delivery policy
Choose your path
Reproduce same-duration target frame-slot and same-frame-count interpreted-duration arithmetic from exact reviewed rational rates without choosing a media conversion method.
Separate a target timeline's frame-slot arithmetic from a clip interpretation that preserves source frames and changes duration.
Name the media inspection and timeline records, copy the exact rational rates, whole frame count and duration, then compare each model with its independent worksheet.
Can locate a count, rate, duration or model mismatch without receiving a duplicate, blend, optical-flow, conform or retime recommendation.
Preserve 24000/1001 or 30000/1001 exactly instead of rounding metadata to 23.98 or 29.97 and silently selecting timecode behavior.
Enter numerator and denominator from the responsible report, reconcile source duration and retain timecode count mode as an external record.
Gets reproducible rational-rate evidence while variable-frame-rate, timestamps, drop/non-drop timecode and delivery acceptance remain explicit external checks.
Understand why unchanged duration and unchanged frame count answer different questions and why a slot difference is not an edit instruction.
Run integer and 1000/1001 exercises, positive/negative comparisons and error boundaries, then review the sampling/audio/timecode checklist.
Can explain both formulas and identify which media, timeline and editorial decisions the calculator deliberately does not make.
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
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Copy each rate as an exact positive rational from its named record. For example, 24000/1001 is preserved instead of rounded to 23.98. A rate does not by itself establish variable-frame-rate behavior, timestamps, endpoint counting, or drop/non-drop timecode.
fps = whole numerator ÷ whole denominatorThe first model holds documented elapsed duration constant and reports a frame-slot equivalent. The second holds the reviewed source-frame count constant and reports interpreted duration. A slot equivalent is not a count of frames to duplicate, drop, blend, or generate.
target slots = documented seconds × target fps; interpreted seconds = source frames ÷ target fpsUse signed slot and duration differences only to locate mismatched count, rational rate, duration, model, or rounding assumptions. Inspect the actual media and verify sampling, cadence, conform, audio, timecode, edit points, render quality, and destination rules separately.
signed difference = reproduced value − independent valueUpdated: August 2026
A reviewed 2,400-frame record at 24/1 fps reproduces 100 seconds. The same documented 100 seconds equals 3,000 target-slot equivalents at 30/1 fps, while preserving 2,400 source frames at 30/1 fps reproduces 80 interpreted seconds. These are two models, not a conversion instruction.
Use 24000/1001 and 30000/1001 as entered whole numerator/denominator pairs. A 2,400-frame source record reproduces 100.1 seconds; that duration corresponds to 3,000 target-slot equivalents, and the same frame count corresponds to 80.08 interpreted seconds.
If reproduced target slots or interpreted duration differ from independent values, preserve the sign and investigate exact rational rates, frame count, source duration, endpoint convention, VFR/timestamp handling, and which model the other worksheet used before changing media.
Reproduce two deliberately separate frame-rate records. Same-duration arithmetic estimates target frame-slot equivalents from documented seconds; same-frame-count arithmetic estimates interpreted duration from a reviewed whole source-frame count. Copy exact rational rates and independent comparison values from responsible records. The result does not inspect media or choose sampling, cadence, conform, timecode, audio, quality, or delivery policy.