How Big Is 70 x 100 cm? | Exact Inches And What Fits

A 70 x 100 cm poster is 27.6 by 39.4 inches, a large format built for bold wall art and promotional displays.

For the full breakdown, see our best 70 X 100 cm Frame guide.

Whether you’re sizing a print for a dorm room or planning a shop display, the question of how big is 70 x 100 cm usually comes down to one thing: will it fit the frame you already own? The short answer is that this metric size translates to roughly 27.5 by 39.4 inches, which puts it in a tricky spot between standard U.S. poster dimensions.

Below is the exact conversion, how it compares to common American sizes, and the one measurement mistake that leads to wasted money on frames.

The Exact Conversion For 70 x 100 cm

Since one inch equals exactly 2.54 cm, the math is straightforward. Dividing 70 by 2.54 gives you 27.5591 inches for the width, and 100 divided by 2.54 gives you 39.3701 inches for the height. That is the precise, unrounded measurement.

In practice, most retailers and print shops round these numbers for simplicity. You will typically see the size listed one of two ways:

• 27.5 x 39.4 inches
• 27.6 x 39.4 inches

Both are acceptable descriptions of the same physical object. The difference of 0.1 inches is well within the manufacturing tolerance of most posters and frames, so either rounded figure works when you are measuring wall space.

For a quick check on any conversion, RapidTables’ cm to inch converter confirms the same result using the standard 2.54 factor.

How It Compares To U.S. Poster Sizes

The biggest source of confusion is assuming this metric size matches the American one-sheet movie poster. It does not. A standard U.S. one-sheet is 27 x 41 inches, which makes it slightly narrower and noticeably taller than the 70 x 100 cm format.

Here is how the dimensions stack up side by side:

This difference matters most when you are shopping for a frame. A frame labeled for a 27 x 40 or 27 x 41 inch print may not fit a 70 x 100 cm poster properly. The 70 cm width is wider than the U.S. standard’s 27 inches, so the poster can bow or buckle inside a frame built for the smaller American size. Always measure the inner opening of a frame rather than trusting the label.

The size is also very close to the ISO B1 standard of 70.7 x 100 cm, but not identical. B1 posters are slightly wider, so assuming the two are interchangeable is a common and costly mistake.

Where This Size Is Typically Used

The 70 x 100 cm format is a large poster size, popular for wall art, concert promotions, and retail advertising. It works equally well in portrait orientation for standing figures or text-heavy designs, and in landscape orientation for wide scenes or banners.

Because of its generous surface area, this format is a favorite for living-room statement pieces and for storefront window displays that need to grab attention from across the street. When you are ready to hang it, the weight of the print and frame means you will typically need wall anchors rated for heavier loads rather than simple nails.

If you are shopping for a ready-made frame, the safest bet is to look for one labeled specifically for 70 x 100 cm prints rather than adapting a U.S. one-sheet frame. This avoids the frustration of a frame that arrives slightly too small for your new print.

Common Mistakes To Avoid

The most frequent errors people make with this size are easy to prevent once you know what to look for.

Confusing it with B1. The ISO B1 standard is 70.7 x 100 cm, which is roughly half a centimeter wider than the print you have. A frame built precisely for B1 may pinch the edges of a 70 cm print.

Rounding with the wrong factor. Some quick mental math shortcuts use 0.39 as the multiplier for converting centimeters to inches. That method gives an approximation, but the exact conversion factor is 1 inch equals 2.54 cm. For a size this large, the rounding error from the shortcut method can shift your measurements by a noticeable fraction of an inch.

Treating 27.6 x 39.4 inches as a universal U.S. standard. While this is the correct conversion, it is not a size you will find on the shelf at most American big-box stores. The U.S. market relies heavily on the 27 x 40 and 27 x 41 inch formats, so you will usually need to order a frame online or from a specialty shop that stocks metric sizes.