QR Code Size Chart — Minimum Sizes for Every Use Case

The 10:1 scanning distance rule and why it determines every QR code size decision

The single most important principle in QR code sizing is the 10:1 ratio rule: the maximum reliable scanning distance is approximately 10 times the width of the QR code. A QR code that measures 3 centimeters across can be scanned from up to 30 centimeters away. A 15 centimeter code scans from up to 1.5 meters. A 50 centimeter code works from 5 meters. This ratio is based on the angular resolution of typical smartphone cameras — the camera sensor needs each QR code module (the smallest square unit in the grid) to occupy a minimum number of pixels in the captured image for reliable detection. As the distance increases, each module occupies fewer pixels until the camera can no longer distinguish between dark and light modules, and the code becomes unscannable.

The 10:1 rule assumes standard conditions: a QR code with moderate data density (Version 3 to Version 7, or roughly 29 to 45 modules per side), good ambient lighting, and a modern smartphone with autofocus. In practice, several factors can reduce this ratio. Poor lighting drops it to roughly 7:1. High data density codes with very small modules drop it to 6:1 or 7:1. Older smartphones with lower-resolution cameras may only manage 8:1. Glossy or reflective surfaces that create glare can reduce effective scanning distance significantly. Conversely, ideal conditions — bright diffused lighting, a low-density code, and a flagship smartphone — can extend the ratio to 12:1 or even 15:1. For reliable sizing, always design for the conservative 10:1 ratio, and treat any additional distance as a bonus rather than a guarantee.

To apply this rule in practice, start with the expected scanning distance and work backward. If you are placing a QR code on a restaurant table tent that diners will scan from about 40 centimeters away, divide by 10 to get the minimum size of 4 centimeters. If the code goes on a tradeshow banner that people will scan from 2 meters, you need at least a 20 centimeter code. If you are printing a billboard QR code meant to be scanned from a car stopped at a traffic light 8 meters away, the code needs to be at least 80 centimeters. Always round up rather than down — there is no penalty for a slightly larger QR code, but a slightly too-small code creates a frustrating user experience that costs you scans and engagement.

Complete size chart: exact dimensions for every use case

Business cards are the most size-constrained QR code application. The standard recommendation is 15 to 20 millimeters (0.6 to 0.8 inches). At 15 mm, the code is scannable at arm's length (20 to 30 cm) but only if the data payload is small — a short URL or a dynamic QR code redirect. At 20 mm, you gain a comfortable margin that accommodates slightly longer URLs and older phone cameras. Never go below 15 mm on a business card. To maximize scannability at these small sizes, use a dynamic QR code (which always encodes a short redirect URL), set error correction to Level M rather than H (to keep module count lower), and ensure the code is printed at 300 DPI or higher. Stickers follow a similar logic at 2 to 3 centimeters, since they are also scanned from close range.

Flyers and brochures are typically viewed at arm's length to about half a meter, which means the QR code should be 2.5 to 4 centimeters (1 to 1.6 inches). A 3 cm code is the sweet spot for most A4 or letter-size flyers — it is large enough to scan reliably, small enough to fit into the design without dominating the layout, and provides a comfortable scanning experience at typical reading distance. For tri-fold brochures where space is tighter, 2.5 cm is acceptable if the data payload is kept small. Table tents and menu cards used in restaurants and cafes need 3 to 5 centimeters because they sit on the table and are scanned from a slightly greater distance (30 to 50 cm) and sometimes at an angle. Product packaging varies widely: small packages like cosmetics or food items need 1.5 to 3 centimeters, while larger packages can accommodate bigger codes.

Posters and signage designed for viewing at 1 to 2 meters require 10 to 15 centimeters (4 to 6 inches). An A3 or A2 poster in a storefront window, transit shelter, or conference hallway should have a QR code of at least 10 cm. If the poster will be viewed from the opposite side of a hallway (3 meters), increase to 15 cm or more. Indoor signage mounted on walls at eye level follows the same guidelines. Always consider the typical viewing path — people walking past a poster may be 1 meter away, but people standing in a queue looking at a poster across the room may be 3 to 4 meters away. Size for the farthest common scanning distance, not the closest.

Banners and large-format displays need 20 to 40 centimeters (8 to 16 inches). Roll-up banners at trade shows are typically scanned from 1.5 to 3 meters, so 20 to 30 cm is appropriate. Hanging banners in event spaces or retail stores viewed from 3 to 5 meters need 30 to 40 cm. Billboards and building-side advertisements represent the extreme end of the scale at 50 centimeters to 1 meter or more. Highway billboards meant to be scanned from vehicles (not recommended for safety reasons, but commonly attempted) need codes of at least 1 meter. Stadium displays and large outdoor advertisements should be 50 to 80 cm for pedestrian scanning at 5 to 8 meters. At these large sizes, print resolution is less critical — 72 to 150 DPI is sufficient because the viewing distance compensates for lower resolution.

DPI requirements and print resolution: ensuring every module is crisp

DPI (dots per inch) determines how sharply each QR code module is rendered in print. The fundamental requirement is that each module must be at least 3 printer dots wide to create clean, distinct edges between dark and light areas. If modules are only 1 or 2 dots wide, ink spread (dot gain) causes dark modules to bleed into light modules, effectively merging them and making the code unscannable. At 300 DPI, each module in a 3 cm QR code with 33 modules per side is approximately 10 dots wide — well above the 3-dot minimum. At 150 DPI, the same module is about 5 dots wide, still adequate but with less margin. At 72 DPI, each module drops to roughly 2.5 dots, which is below the safe threshold for close-range printing.

For materials scanned at close range — business cards, flyers, brochures, product packaging, and stickers — always print at 300 DPI. This resolution ensures razor-sharp module edges and maximum contrast between dark and light areas, both of which directly improve scan speed and reliability. If your print provider offers higher resolution (600 or 1200 DPI), use it — there is no downside to higher resolution for QR codes. The key is to export your QR code as a vector file (SVG or PDF) so the print driver renders it at the native printer resolution rather than rasterizing it at a lower resolution. Vector QR codes produce the sharpest possible output regardless of print size or DPI setting.

For large-format printing — posters, banners, and billboards — the DPI requirement drops because the viewing distance is greater. A poster printed at 150 DPI looks sharp from 1 meter away, even though the individual dots would be visible under a magnifying glass. Banners typically print at 100 to 150 DPI, and billboards at 72 to 100 DPI. At these resolutions, a 15 cm QR code with 33 modules per side still has each module rendered at 7 to 10 dots wide at 150 DPI, which is perfectly adequate. The important consideration for large-format printing is the print substrate — vinyl banners, fabric, and outdoor materials can cause ink spread that effectively reduces resolution. Request a proof print and test the QR code scannability before committing to a full production run, especially for expensive large-format orders.

Module density and data payload: how encoded content changes size requirements

The amount of data encoded in a QR code directly determines the number of modules in the grid, which in turn affects the minimum viable physical size. A QR code is built on a grid that ranges from Version 1 (21 by 21 modules) to Version 40 (177 by 177 modules). Each version adds 4 modules per side. A short URL of 20 characters might fit in a Version 2 code (25 by 25), while a full vCard with name, phone, email, address, and company might require Version 10 (57 by 57) or higher. At the same physical size, a Version 10 code has modules that are less than half the width of a Version 2 code, making them much harder for cameras to resolve.

This relationship between data payload and physical size is the reason the first recommendation in every QR code sizing guide is to minimize the encoded data. A dynamic QR code solves this elegantly — it always encodes a short redirect URL (typically 20 to 30 characters) regardless of where it ultimately redirects. This keeps the module count low, which keeps individual modules large, which means the code can be printed smaller while remaining scannable. If you must use a static QR code, shorten your URL using a service, remove unnecessary tracking parameters, and use the shortest possible domain. Every character you remove allows a lower version code with larger modules.

Error correction level also affects module density. Level L adds the least redundant data and produces the smallest code for a given payload. Level H adds the most redundancy and produces the densest code. For a 50-character URL, the difference between Level L and Level H can be an entire version step — say Version 4 (33 by 33) at Level L versus Version 5 (37 by 37) at Level H. When size is constrained, like on a business card or small packaging, consider using Level M instead of Level H if you are not adding a logo. Level M provides 15 percent error recovery, which is sufficient for most printed materials in good condition. Reserve Level H for codes with logos or codes that will be exposed to wear, dirt, or damage.

To put this in practical terms, a business card QR code at 15 mm with a Version 2 grid has modules approximately 0.6 mm each — scannable but at the limit for most cameras. The same 15 mm code at Version 5 has modules of only 0.4 mm, which many cameras struggle with. At Version 8, the modules drop to 0.3 mm and the code becomes unreliable at that size. This is why data payload and size are inseparable considerations. If you need a small QR code, you must keep the data small. If you need to encode a lot of data, you must make the code physically larger. There is no way around this fundamental relationship between information density and physical dimension.