| Mode | What the capacity counts | Version 1, level L |
|---|---|---|
| Numeric | Decimal digits | 41 digits |
| Alphanumeric | Restricted uppercase character set | 25 characters |
| Byte | Encoded bytes | 17 bytes |
| Kanji | Characters in the supported Kanji encoding | 10 characters |
Choose content before choosing capacity
The QR symbol format and the application payload are different layers. A WiFi credential string, a calendar event and a URL can all be stored in byte mode, even though a phone may offer a different action for each. The scanner decodes bytes first; an application then interprets the text convention.
Numeric and alphanumeric modes can pack suitable input more tightly than byte mode. That does not mean you should uppercase a URL to make it fit. Paths and query values can be case-sensitive, so changing case can change the destination or break a signed link.
Count the bytes you actually encode
UTF-8 represents some characters with more than a single byte. Accented letters, non-Latin scripts and emoji can therefore increase the payload size faster than a visible character counter suggests. Percent-encoding in a URL can also expand the string before it reaches the QR encoder.
Structured formats add their own syntax. A contact code includes property names and line endings, while a calendar event includes timestamps and identifiers. The useful information may be short even though the serialized payload is longer. Inspect the exact encoded content when investigating an unexpectedly dense symbol.
Simplify without losing meaning
For a website, remove unnecessary tracking parameters only when you understand their purpose and have tested the resulting URL. A stable short path on a domain you control can be useful. An arbitrary third-party short link introduces another service dependency that you should evaluate explicitly.
For an offline message, keep the wording focused. If the content is too long, choose a hosted page and make the network requirement clear. Do not split data across multiple QR codes unless the receiving workflow is designed to reassemble it. The ordinary phone camera is not a general multi-part document importer.
Put this into practice in the QR generator, then inspect the decoded payload before printing.
Sources
Last checked: . Examples are illustrative inputs, not measured results.
- QR Code versions and information capacity, DENSO WAVE. Checked 2026-10-29.
- Capacity table: versions 1 to 10, DENSO WAVE. Checked 2026-10-29.
- Barcode Contents, ZXing project. Checked 2026-10-29.