How much information can a barcode encode?

There are many different types of barcode formats (known as barcode symbologies) and each has its own limitations. Fixed length barcodes such as EAN-13 allow only 13 characters to be encoded, while Code 39 and Code 128 are variable length barcodes and are typically limited only by the size available for barcode placement. Generally, the more data that is encoded, the longer the resultant barcode will be. Barcode scanners also have scan range size limitations that may limit the maximum size of a barcode in a particular application. In practice, most popular variable length 1D barcodes can encode up 64 characters, while 2D barcodes can encode up to 1600 characters or more.