Reproduce reviewed square-pixel active-image geometry for a documented target canvas using an explicit Fit/Pad or Fill/Crop mode and rounding rule.
Use this result well
Inputs that matter
One de-identified reviewed canvas record; named source active-image, square-pixel normalization, target-canvas, geometry-mode, rounding and independent-geometry records; positive whole source and target dimensions; and nonnegative independent rounded dimensions
Output to expect
Simplified source and target ratios, selected fit/pad or fill/crop mode, continuous and documented-rounded scaled dimensions, signed horizontal and vertical canvas differences, and signed differences from the independent geometry
How it works
For Fit/Pad use the smaller target-to-source axis scale; for Fill/Crop use the larger scale. Apply only the selected rounding rule to each continuous scaled dimension, subtract the rounded image from the target canvas so positive values mean pad extent and negative values mean crop overflow, and compare the rounded dimensions with the independent record
Confirm the source record identifies the active image rather than only storage raster, and verify sample/pixel aspect ratio, clean aperture or display matrix, orientation and any prior crop before using the square-pixel dimensions.
Verify the chosen conform mode, crop or border allocation, anchor, safe area, reframing, codec/chroma divisibility, target resolution, platform or delivery specification and visual result separately in the responsible application.
Choose your path
Built around the job you need to finish
Reproduce user-selected fit/pad or fill/crop canvas geometry from reviewed square-pixel active-image and target-canvas dimensions without choosing a conform or delivery policy.
Video editor reconciling an active image with a sequence canvas
Know the exact scaled raster and pad or crop extent for a conform mode already chosen in the edit plan.
Name the media-inspection and sequence records, copy reviewed square-pixel active-image and canvas dimensions, select Fit/Pad or Fill/Crop and the documented rounding rule, then compare the result with the application's geometry.
Can locate a source, mode or rounding mismatch without receiving an anchor, crop-edge, safe-area, reframing or export recommendation.
Media operations specialist checking raster metadata
Avoid treating stored width and height as display geometry when sample aspect, aperture, orientation or prior cropping changes the active image.
Normalize the inspected record to named square-pixel active dimensions outside the worksheet, retain that normalization provenance, then reproduce both axis differences against the reviewed target canvas.
Gets traceable signed pad/crop evidence while sample-aspect interpretation, metadata repair, codec divisibility and delivery acceptance stay with the responsible workflow.
Post-production trainee learning conform geometry
Understand why Fit and Fill use different scale factors and why one total signed extent does not choose where borders or crop are placed.
Run square and widescreen exercises with continuous, floor, nearest and ceiling rounding, then compare an independently calculated geometry and review the excluded decisions.
Can explain the scale, rounding and signed differences without confusing arithmetic with a creative or technical approval.
Authoritative checks for this tool
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.
Enter positive whole square-pixel dimensions copied from named records. Storage raster alone may not establish display geometry when sample aspect ratio, clean aperture, display matrix, orientation or prior cropping changes the active image. Normalize and document those properties in the responsible inspection workflow before using this arithmetic.
source ratio = active width ÷ active height; target ratio = canvas width ÷ canvas height
Apply the Selected Conform Mode
Fit/Pad preserves the complete rectangular source within the canvas and can leave positive pad extent. Fill/Crop covers the canvas and can produce negative overflow that must be cropped. The worksheet reproduces the selected mode; it does not decide which visual tradeoff is acceptable.
Apply only the selected continuous, floor, nearest or ceiling rule to both scaled dimensions. Positive canvas difference means total available pad extent on that axis; negative means total crop overflow. Neither total chooses an edge split or anchor. Preserve signed comparison differences to locate source, mode or rounding mismatches.
A reviewed 1920×1080 square-pixel active image fitted into a 1080×1080 canvas uses scale 0.5625. Nearest rounding gives 1080×608, zero horizontal difference and +472 pixels of total vertical pad extent. The worksheet does not choose how that extent is split.
Using Fill/Crop with the same 1920×1080 source and 1080×1080 canvas uses scale 1 and gives 1920×1080, with −840 pixels of total horizontal crop overflow and zero vertical difference. An anchor or crop-edge allocation still requires visual review.
Enter an independent scaled width and height from a responsible application or worksheet. A nonzero signed comparison can identify a different active image, pixel-aspect normalization, conform mode or rounding rule; it does not prove which record is correct.
FAQ
No. Sample or pixel aspect ratio, clean aperture, display matrix, orientation and prior cropping can affect displayed or active-image geometry. This worksheet deliberately requires a named square-pixel active-image record.
No. It reports the total positive canvas difference for each axis. Border distribution, background treatment, anchor and safe area are external creative and delivery decisions.
No. It reports total negative overflow on each axis. Crop allocation, anchor, subject protection, content-aware reframing and shot-by-shot review belong in the responsible editing workflow.
No. Floor, nearest and ceiling reproduce only a documented integer-rounding rule. Codec, chroma-subsampling, encoder, hardware and container constraints can impose separate divisibility or alignment requirements.
No. Target resolution, frame rate, color, safe areas, pixel aspect, codec, bitrate, metadata and acceptance rules must come from the current destination specification and be verified in the actual export.
About Aspect Ratio Calculator
Reproduce one documented canvas-geometry decision. Copy the reviewed square-pixel active-image dimensions and target-canvas dimensions, select the already-approved Fit/Pad or Fill/Crop mode and the rounding rule used by the responsible workflow, then compare the rounded result with an independent geometry record. The worksheet does not inspect media, normalize pixel aspect ratio, choose crop placement, or approve a platform or delivery format.