PostMicroTools
Calculator
Aspect ratio + previewer
Work out the aspect ratio of a resolution, resize keeping proportion, and see how your footage fits into another format (letterbox/pillarbox) with safe areas.
My saved presets PRO
Your cloud-synced presets for this tool. Load, delete or save new ones with the button above.
Loading…
Common aspect ratios
16:9 is the TV and web standard; 2.39:1 (scope) and 1.85:1 (flat) are cinema formats; 9:16, 4:5 and 1:1 dominate social media. Moving footage between formats adds bars (letterbox/pillarbox) or crops, so it pays to frame with safe areas in mind.
What are safe areas?
Inner margins that guarantee action (action safe, ~90%) and text/graphics (title safe, ~80%) aren't lost to screen cropping or reframing. They come from the CRT era but remain useful for multi-format delivery.
Why 2.39 and not 2.40?
Modern scope is specified as 2.39:1 (formerly 2.35:1). It's often rounded to 2.40 in conversation, but the delivery value is 2.39:1.
From scope masters to vertical cutdowns
The daily use case is fitting one aspect ratio inside another without guessing. A 2.39:1 scope picture delivered inside a UHD 16:9 container occupies 3840×1607, leaving letterbox bars of about 276 px top and bottom — numbers you need exactly when building delivery masters or checking that a vendor's bars are symmetrical.
The reverse trip matters just as much now: cutting 9:16 vertical deliverables from a 16:9 master means only a 608 px-wide slice of a 1080p frame survives, which is why social cutdowns are reframed shot by shot rather than center-cropped. The visual letterbox/pillarbox preview shows instantly how much image each strategy sacrifices.
Action-safe and title-safe overlays (90% / 80% of frame height in the classic broadcast convention) are included because lower-thirds still get cut off on overscanning TVs and on platform UIs that lay controls over the picture edges.
What resolution is 2.39:1 inside a UHD frame?
3840×1607 (usually rounded to 1608 for an even number). In 1080p it's 1920×803/804. The calculator gives the exact height for any width and ratio, plus the bar sizes.
How does anamorphic desqueeze fit in?
A 2× anamorphic lens on a 4:3 sensor yields a 2.66:1 image once desqueezed; on a 16:9 sensor it gives 3.55:1, which is why 1.3× and 1.5× squeeze factors exist. Enter the desqueezed dimensions here to plan the extraction.
Is title-safe still a thing on streaming?
Less rigid than broadcast, but yes in practice: platform UIs overlay progress bars and buttons near the frame edges, and TV overscan hasn't fully disappeared. Keeping critical text inside roughly 90% of the frame remains the safe habit.