How much data can a QR code fit?
March 7, 2025 by @anthonynsimon
A QR code is a type of barcode that can be read by digital devices. It has a grid of small squares (modules) that represent a sequence of bits (0s and 1s). The arrangement of these squares encodes information, which can be anything from a simple URL to complex data like contact details or Wi-Fi passwords.
The smallest standard QR code has 21×21 modules, while the largest has 177×177. Having more squares means it can hold more data.
Here's an approximation of how many characters you can fit in a QR code, depending on its size and error correction level:
| Version | Size | Low (L) | Medium (M) | Quartile (Q) | High (H) |
|---|---|---|---|---|---|
| 1 | 21×21 | ~25 characters | ~20 characters | ~16 characters | ~10 characters |
| 10 | 57×57 | ~175 characters | ~140 characters | ~100 characters | ~80 characters |
| 25 | 117×117 | ~1,500 characters | ~1,200 characters | ~850 characters | ~700 characters |
| 40 | 177×177 | ~3,000 characters | ~2,300 characters | ~1,600 characters | ~1,200 characters |
What kinds of data can QR codes hold?
A large (177×177) QR code can hold about 15,000 bits of data, which could be around 2,000 characters of text depending on the encoding and error correction level. This is enough to store a short paragraph or a long URL.
Below is a rough guide to what can fit inside a single QR code:
| Type of Data | Example Size | Will it Fit in a QR Code? |
|---|---|---|
| A full blog post | ~2,000 characters (short article) | Yes, in a large code (177×177) |
| YouTube URLs | ~10–30 characters per link | Yes, many standard codes can handle this easily |
| Links to multiple videos | Multiple short URLs in one QR code | Yes, if you compress or use a URL shortener |
| Wi-Fi login info | 20–40 characters (network & password) | Yes, even in a smaller code |
| Small image as raw data | Under ~2 KB of data | Possibly, but usually better to store an image link |
| Book (e.g. 50,000+ words) | ~300,000+ characters in a typical novel | Not directly (exceeds capacity), but a link to a PDF works |
QR codes also use four levels of error correction (L, M, Q, H). Error correction lets the QR code still work if part of it is damaged, although it slightly reduces how much data it can store.
Even with the highest level of error correction, a QR code could still fit a link to a website, store contact details, short paragraphs, or Wi-Fi passwords. Even smaller QR codes, like 32×32, have enough capacity for many use cases.
Conclusion
In short, while QR codes may seem small, they can hold a surprising amount of data. Their combination of dense storage, error correction, and ease of scanning allows them to serve many purposes, from linking to websites and videos to encoding Wi-Fi passwords and more.