Koha by the numbers
Koha uses unique numbers to track important records on the system. Below is a table with documents outlining some of the different numbers that are used and where they can be found. Click through the different tabs to view details on the different numbers you might encounter when cataloguing, reporting or working with patron records.
Biblionumbers
Itemnumbers
Barcodes
Borrowernumbers
Cardnumbers
Biblionumbers
What is a biblionumber?
Biblionumbers are unique numbers automatically applied by Koha to bibliographic records created on the system. These numbers are assigned as title records are created and cannot be edited from within the Koha application. The function of a biblionumber is to act as an identification number for a title record.
How can a biblionumber be identified?
URL
On a bibliographic record the biblionumber is in the URL:
Reports
There are many different reports that can bring back the biblionumbers on records. A basic setup would be:
SELECT biblionumber, title
FROM biblio
LIMIT 10
This report will bring back results similar to the image below:
This basic report can be limited in an almost unlimited number of ways, including by a specific title, collection codes and date added to the site.
As all title records will have biblionumbers an unlimited report should not be run as the resources used to bring back the result might slow the system.
For assistance in creating a report to bring back a specific biblionumber, please check our support site or contact Interleaf Technology directly.
| Version | Date | Detail | Author |
| 1.0 | 11/12/25 | Document created | Holly Cooper |
| 1.1 | 29/12/25 | Adding details | Holly Cooper |
| 1.2 | 28/04/26 | Adding details | Holly Cooper |
Itemnumbers
What are item numbers?
Item numbers are unique internal database numbers applied to all items on a Koha system. Unlike barcodes, which are assigned by the library, these are automatically generated by the system as items are created. These numbers do not show in the item record, unless their field is set to appear, which it is strongly advised not to do. Itemnumber fields should not be set to appear in the item record because that would allow them to be edited, which could cause catastrophic and potentially irreversible problems for the database.
What are they used for?
The main use for item numbers is to link different tables within the SQL database.
How can they be found?
It is not usually possible to search the catalogue by item number as it is not something that most users think about and seek to identify, however they can be found by running particular SQL queries. An example of such a report is:
SELECT items.itemnumber, items.barcode
FROM items
It should be noted that this is the report at its most basic and if there are many items on the catalogue it could slow the system searching for them.
For advice about the different ways to limit reports, please check our Help Centre for report information or contact Interleaf Technology directly.
| 2.3 | 28/11/25 | Updating for newer version of Koha | Holly Cooper |
Barcodes
What are barcodes?
Barcodes are unique numbers, manually applied to all items on a Koha system. Unlike item numbers, which are automatically generated by the system as items are created these are assigned by the library as item records are created. Generally, barcodes appear on the item records, unless they have been set to be hidden.
For more details on hiding and revealing fields on the item record field, please check our Help Centre or contact Interleaf Technology directly.
What are they used for?
The main use for barcodes is to allow individual items to be checked out to patrons on the system. They can also be used to identify records within the SQL database.
How can they be found?
Barcodes can be found on item records and specific barcodes can be searched through the catalogue.
Barcodes can also be found through SQL report, for example:
SELECT items.barcode
FROM items
It should be noted that this is the report at its most basic and if there are many items on the catalogue it could slow the system searching for them.
For advice about the different ways to limit reports, please check our Help Centre for report information or contact Interleaf Technology directly.
Borrowernumbers
What is a borrowernumber?
Borrowernumber are unique numbers that are automatically applied to new patron records by the Koha site as they are created. The borrowernumber must be unique and it cannot be edited from within the Koha application. The function of a borrowernumber is to act as an identification number for the patron record.
How can a borrowernumber be identified?
Patron Account
On a patron record, the borrowernumber can be seen in the Library use section of the patron account.
Reports
There are many different reports that can bring back the borrowernumber on records. A basic setup would be:
SELECT borrowernumber
FROM borrowers
LIMIT 10
This report will bring back results similar to the image below:
This basic report can be limited in an almost unlimited number of ways, including by patron category, registration date and home branch.
As all patron accounts will have a borrowernumber an unlimited report should not be run as the resources used to bring back the result might slow the site
For assistance in creating a report to bring back a specific borrowernumber or range of borrowernumbers, please contact Interleaf Technology directly.
| Version | Date | Detail | Author |
| 1.0 | 09/01/26 | Document created | Holly Cooper |
Cardnumbers
What is a cardnumber?
Cardnumbers are unique numbers that are manually applied to new patron records by the staff member creating the patron record. They do not necessarily need to come from a physical card. The cardnumber must be unique but it can be edited at any time through the staff side of Koha. The function of a cardnumber is to act as an identification number for the patron record and the hook to complete and track circulation actions through.
How can a cardnumber be identified?
Patron Account
On a patron record, the cardnumber can be seen in the Library use section of the patron account.
Reports
There are many different reports that can bring back the cardnumbers on records. A basic setup would be:
SELECT cardnumber
FROM borrowers
LIMIT 10
This report will bring back results similar to the image below:
This basic report can be limited in an almost unlimited number of ways, including by patron category, registration date and home branch.
As all patron accounts will have a cardnumber an unlimited report should not be run as the resources used to bring back the result might slow the site
For assistance in creating a report to bring back a specific cardnumber or range of cardnumbers, please contact Interleaf Technology directly.
| Version | Date | Detail | Author |
| 1.0 | 29/01/26 | Document created | Holly Cooper |
What are biblionumbers and how to find them?
What are biblionumbers and how to find them?
What is a biblionumber?
Biblionumbers are unique numbers automatically applied by Koha to bibliographic records created on the system. These numbers are assigned as title records are created and cannot be edited from within the Koha application. The function of a biblionumber is to act as an identification number for a title record.
How can a biblionumber be identified?
URL
On a bibliographic record the biblionumber is in the URL:
Reports
There are many different reports that can bring back the biblionumbers on records. A basic setup would be:
SELECT biblionumber, title
FROM biblio
LIMIT 10
This report will bring back results similar to the image below:
This basic report can be limited in an almost unlimited number of ways, including by a specific title, collection codes and date added to the site.
As all title records will have biblionumbers an unlimited report should not be run as the resources used to bring back the result might slow the system.
For assistance in creating a report to bring back a specific biblionumber, please check our support site or contact Interleaf Technology directly.
| Version | Date | Detail | Author |
| 1.0 | 11/12/25 | Document created | Holly Cooper |
| 1.1 | 29/12/25 | Adding details | Holly Cooper |
| 1.2 | 28/04/26 | Adding details | Holly Cooper |
Is there a number you have seen on Koha and you don't know what it relates to? Let us know and we will add it to our resource!
| Version | Date | Detail | Author |
| 1.0 | 28/04/26 | Document created | Holly Cooper |
Related Articles
What are item numbers and how can they be identified?
What are item numbers? Item numbers are unique internal database numbers applied to all items on a Koha system. Unlike barcodes, which are assigned by the library, these are automatically generated by the system as items are created. These numbers do ...What are biblionumbers and how to find them
What is a biblionumber? Biblionumbers are unique numbers automatically applied by Koha to bibliographic records created on the system. These numbers are assigned as title records are created and cannot be edited from within the Koha application. The ...What are barcodes and how can they be identified?
What are barcodes? Barcodes are unique numbers, manually applied to all items on a Koha system. Unlike item numbers, which are automatically generated by the system as items are created these are assigned by the library as item records are created. ...How to make barcodes appear on the OPAC
Item barcodes do not display by default on the OPAC but it is possible to enable them with the following steps. Find configure columns Go to Koha administration > Additional parameters > Table settings. This will take you to a new page with several ...What are borrowernumbers and how to find them?
What is a borrowernumber? Borrowernumber are unique numbers that are automatically applied to new patron records by the Koha site as they are created. The borrowernumber must be unique and it cannot be edited from within the Koha application. The ...