Manga Aspect Ratio & Wallpaper Crop Resizer
Calculate simplified aspect ratios, dual-page spread stitching dimensions, and lossless wallpaper cropping boundaries for modern mobile and desktop screens.
Dimension Inputs
Enter current canvas pixels and select your target viewing device.
Manga Page Geometry & The Silver Ratio
Japanese paper formats (including standard JIS B6 and ISO A5) are constructed on the Yamato ratio or Silver Ratio: 1 : √2 (approximately 1 : 1.414). This mathematical property allows a page to be halved or doubled (such as combining two single pages into a two-page double spread) while preserving the exact same geometric aspect ratio proportions.
Greatest Common Divisor = GCD(Width, Height)
Simplified Ratio = (Width ÷ GCD) : (Height ÷ GCD)
Two-Page Double Spread Ratio = (2 × Single Width) : Single Height = ~1.414 : 1
Device Screen Aspect Ratio Comparison
| Device Class | Screen Ratio | Manga Compatibility | Letterbox / Pillarbox Effect |
|---|---|---|---|
| Apple iPad / Android Tablets (4:3) | 4:3 (1.33) | Near Perfect Match (94% screen fill) | Minimal vertical pillarboxing |
| Modern Smartphones (19.5:9, 20:9) | 19.5:9 (2.16) | Taller than single manga pages | Significant black bars top & bottom unless zoomed |
| Desktop / Laptop Displays (16:9) | 16:9 (1.77) | Ideal for Two-Page Double Spreads | Single pages produce wide side pillarbox margins |
| Amazon Kindle Paperwhite | 4:3.05 (~1.35) | Native Tankobon Fit | Full-screen zero distortion fill |
Frequently Asked Questions
In physical tankobons, double spreads lose 2–5mm of artwork inside the binding spine gutter. When stitching digitized pages, ensure the right page (Japanese reading order page 1) is placed on the right and left page on the left. If physical scanning produced curved inner margins, de-skew the inner edges and stitch with a 15–30px overlap to align horizontal dialogue lines.