Size Comparisons, Drawn to the Same Scale

Spec sheets give you numbers. Jissun Lab draws those numbers as shapes on one shared scale, so you can see how much bigger, taller or narrower one thing is than another before you buy, print, pack or ship it. Dimensions come from official standards and makers' published specs, and every page lists its sources.

Featured: A4 vs Letter

Paper & Print

• A4 vs LetterA4 8.27×11.69 in (210×297 mm) / Letter 8.5×11 in (215.9×279.4 mm)A4 is 0.23 in narrower and 0.69 in taller than Letter.
• Tabloid (11x17) vs A3Tabloid 11×17 in (279.4×431.8 mm) / A3 11.69×16.54 in (297×420 mm)A3 is 0.69 in wider; Tabloid (also called Ledger) is 0.46 in taller. Neither fits inside the other.
• ANSI Paper Sizes A–EA 8.5×11 in / B 11×17 in / C 17×22 in / D 22×34 in / E 34×44 inThe five sizes nest inside each other, but the aspect ratio alternates between 17:22 (A, C, E) and 11:17 (B, D) — not the constant 1:√2 of ISO A.
• Arch Paper Sizes A–EA 9×12 in (228.6×304.8 mm) / B 12×18 in / C 18×24 in / D 24×36 in / E 36×48 in (914.4×1219.2 mm)Each Arch size is larger than its ANSI counterpart. Arch A is 0.5 in wider and 1 in taller than ANSI A; by Arch E, the difference grows to 2 in wider and 4 in taller.
• Photo Print Sizes: 4×6, 5×7, 8×10, 11×14, 16×204×6 in 102×152 mm (3:2) / 5×7 in 127×178 mm (7:5) / 8×10 in 203×254 mm (5:4) / 11×14 in 279×356 mm (14:11) / 16×20 in 406×508 mm (5:4)Four different shapes among the five sizes, so moving a photo between them means cropping or white borders; 8×10 to 16×20 is the one enlargement with no crop.
• Poster Sizes: 18×24, 24×36 and 27×40 in18×24 in 457×610 mm (3:4) / 24×36 in 610×914 mm (2:3) / 27×40 in 686×1016 mm (one-sheet)24×36 is exactly twice the area of 18×24. 27×40 is 3 in wider and 4 in taller than 24×36 and does not fit a 24×36 frame.
• US Envelope Sizes: #10, #9, #6¾, A2, A7#10 4 1/8×9 1/2 in (104.8×241.3 mm) / #9 3 7/8×8 7/8 in (98.4×225.4 mm) / A7 5 1/4×7 1/4 in (133.4×184.2 mm)#10 holds a Letter sheet folded in thirds; #9 fits inside a #10 as a reply envelope; A7 is the standard for 5×7 in invitations.
• 9×12 vs 10×13 Catalog Envelopes9×12: 9×12 in (228.6×304.8 mm) / 10×13: 10×13 in (254×330.2 mm)Both hold a US Letter sheet flat. The 9×12 leaves 0.25 in on each side; the 10×13 leaves 0.75 in — 3× the clearance for thicker packs.

Tech & Handhelds

• PS5 Slim vs Xbox Series X SizePS5 Slim 3.78×14.09×8.50 in (96×358×216 mm) / Xbox Series X 5.94×11.85×5.94 in (151×301×151 mm)Upright, PS5 Slim is 2.17 in narrower but 2.24 in taller. Laid flat, PS5 Slim is 2.24 in wider and 2.56 in deeper.
• iPhone 17 vs Air vs Pro vs Pro Max SizeiPhone 17 5.89×2.81 in (149.6×71.5 mm) / Air 6.15×2.94 in (156.2×74.7 mm) / Pro 5.91×2.83 in (150.0×71.9 mm) / Pro Max 6.43×3.07 in (163.4×78.0 mm)Pro Max is tallest, widest and heaviest (233 g); Air is thinnest (5.64 mm) and lightest (165 g); 17 and Pro differ by just 0.4 mm in height and width.
• Switch 2 vs Switch OLED vs Steam DeckSwitch 2 10.71×4.57 in (272×116 mm) / Switch OLED 9.53×4.02 in (242×102 mm) / Steam Deck OLED 11.73×4.61 in (298×117 mm)Steam Deck OLED is widest and deepest (49 mm overall); Switch 2 and Switch OLED share the same 13.9 mm body depth.
• 24 vs 27 vs 32 Inch Monitor Size24 in: 20.92×11.77 in (531×299 mm) / 27 in: 23.53×13.24 in (598×336 mm) / 32 in: 27.89×15.69 in (708×398 mm)32 in is 77.8% larger in area than 24 in; all values calculated from the 16:9 diagonal formula.
• iPad Air vs iPad Pro Size: 11 and 13 Inch ComparedAir 11: 9.74×7.02×0.24 in (247.6×178.5×6.1 mm) / Pro 11: 9.83×6.99×0.21 in (249.7×177.5×5.3 mm) / Air 13: 11.04×8.46×0.24 in (280.6×214.9×6.1 mm) / Pro 13: 11.09×8.48×0.20 in (281.6×215.5×5.1 mm)Footprints are nearly identical within each size class. The Pro is thinner: 0.8 mm in the 11-inch and 1.0 mm in the 13-inch.

Travel & Shipping

• In-Cabin Pet Carrier Size18×11×11 in (Delta, United, AA) / 18×14×11 in (Frontier) / 17×12.5×8.5 in (JetBlue) / 17×11×9.5 in (Alaska)Seven US airlines' in-cabin soft-sided and hard-sided pet carrier size limits drawn to the same scale, with a full side-by-side table.
• Carry-On vs Personal Item Size22×14×9 in (Delta, United, AA, JetBlue, Alaska, Hawaiian) / 24×16×10 in (Southwest, Frontier) / 22×16×10 in (Allegiant)Nine US airlines' carry-on and personal item limits, the one published weight limit (Frontier, 35 lb), and a table that checks your own bag's three sides against each airline.
• Checked Bag Size Limits62 linear in (157 cm) / 50 lb (23 kg) — 8 of 9 airlines; Frontier 40 lb; Allegiant 80 linear inNine US airlines' checked bag size and weight limits from their official policy pages. Eight airlines cap bags at 62 linear inches (L+W+H); Allegiant allows 80 linear inches; Frontier's weight limit is 40 lb instead of the standard 50 lb.
• USPS Flat Rate Box Sizes: Interior vs ExteriorSmall interior 8 5/8×5 3/8×1 5/8 in / Medium 1 interior 11×8 1/2×5 1/2 in / Medium 2 interior 13 5/8×11 7/8×3 3/8 in / Large interior 12×11 3/4×5 1/2 inMedium 1 and Large lose 1/4 in total in width and in depth, and 1/2 in total in height, to the cardboard walls. Medium 2 loses 3/8, 1/8 and 1/8 in.
• USPS Postcard Size LimitsMin 3.5×5 in (88.9×127 mm) / Max 4.25×6 in (107.95×152.4 mm)Minimum and maximum size for First-Class Mail postcard rate, drawn to the same scale. Cards larger than 4.25×6 in pay Letter rate; cards over 6×9 in are flats.
• FedEx vs UPS Express Box SizesFedEx Small interior 12 3/8×10 7/8×1 1/2 in / FedEx Large interior 17 1/2×12 3/8×3 in / UPS Small exterior 13×11×2 in / UPS Large exterior 18×13×3 inFedEx and UPS branded express boxes drawn to the same scale. UPS Large is 0.5 in wider than FedEx Large flat. Also compares footprint to USPS Flat Rate boxes.
• Moving Box Sizes: Small to WardrobeSmall 16×12×12 in (406×305×305 mm) 1.5 cu ft / Medium 18×16×16 in 3.0 cu ft / Large 24×18×18 in 4.5 cu ft / XL 24×20×21 in 5.8 cu ft / Wardrobe 24×24×40 in 13.3 cu ftAll five standard moving box sizes drawn to the same scale. Wardrobe box includes a hanging bar for clothes; XL note covers the 24×20×21 (Home Depot) and 24×20×24 variants.

Home & Living

• Mattress Sizes: Twin to California KingTwin 38×75 in (965×1905 mm) / Queen 60×80 in (1524×2032 mm) / King 76×80 in (1930×2032 mm) / Cal King 72×84 in (1829×2134 mm)Cal King is 4 in narrower and 4 in longer than King. Sealy, Serta and Casper list the Full at 53 in wide, not the nominal 54 in.
• Area Rug Sizes: 5×7, 8×10, and 9×12 ft5×7 ft 60×84 in (1524×2134 mm) 35 ft² / 8×10 ft 96×120 in (2438×3048 mm) 80 ft² / 9×12 ft 108×144 in (2743×3658 mm) 108 ft²9×12 covers 3.1× the floor area of a 5×7. All three are nominal trade sizes.
• 2×4 Lumber: Nominal vs Dressed Dry Dimensions (1×4 to 6×6)2×4: 1.5×3.5 in (38×89 mm) / 1×4: 0.75×3.5 in (19×89 mm) / 4×4: 3.5×3.5 in (89×89 mm) / 6×6: 5.5×5.5 in (140×140 mm)Full table 1×2 through 6×6. Nominal names come from the rough green size; drying and surfacing reduce every board below the name. Source: NIST PS 20-25.
• Bankers Box Dimensions: 703 and R-Kive 725703 exterior 12.5×16.3×10.5 in (317.5×414×266.7 mm) / R-Kive 725 exterior 12.8×16.5×10.4 in (325.1×419.1×264.2 mm) / both hold Letter and Legal files insideSTOR/FILE 703 (light duty) and R-Kive 725 (heavy duty) exterior and interior dimensions compared. Both fit Letter (8.5×11 in) and Legal (8.5×14 in) paper flat.
• Sheet Pan Sizes: Full, Half, and QuarterFull 18×26 in (457×660 mm) 468 sq in / Half 17.75×12.75 in (451×324 mm) 226 sq in / Quarter 13×9.5 in (330×241 mm) 123.5 sq inThree standard sizes drawn to the same scale. A half sheet covers roughly half the area of a full sheet; a quarter covers roughly one quarter. Full sheet fits commercial ovens only.
• Cast Iron Skillet Sizes: Rim vs Cooking Surface8 in rim 8.68 in (220 mm) / 10.25 in rim 10.68 in (271 mm) / 12 in rim 12.56 in (319 mm) / 15 in rim 15.0 in (381 mm)Lodge Classic Cast Iron Skillets: the nominal size (8, 10.25, 12 in) matches the cooking surface, not the rim. Rim is 0.43–0.81 in wider than the cooking surface.

How we measure

• Nominal dimensions only, taken from the official standard (ISO, ASME and so on) or the maker's published spec. Where a size is a trade label with no free standard (mattresses, rugs, photo prints), the page says so and names the source it used. Each page lists its sources with the date we checked them.
• Inches first, millimeters alongside. Where a standard writes a fraction (8 1/2 in), we give the fraction too.
• Every shape on a page shares one scale. The drawings are scaled down; they are not shown at real size on your screen.
• Real items vary slightly because of manufacturing tolerances.

日本語版（実寸ラボ）