Image forming apparatus

An image forming apparatus, comprising:

• a print data acquiring unit configured to acquire variable-data-printing print data that includes common document data and insert data, the common document data including a common part common to plural printed matters, the insert data for a variable part individually set for each of the plural printed matters;
• a variable-data-printing processing unit configured to cause a printing device to perform variable data printing on the basis of the variable-data-printing print data;
• wherein the common document data includes one or plural identifiers;
• the identifier indicates the variable part;
• the insert data includes one or plural values corresponding to the identifier;
• the variable-data-printing processing unit causes the printing device to perform the variable data printing on the basis of print data obtained by replacing the identifier in the common document data with the value;
• and
• the variable-data-printing processing unit further determines a print sheet corresponding to the value used in the replacement on the basis of print output characteristic data that indicates a print sheet corresponding to a value of the identifier, and causes the printing device to perform the variable data printing based on the print data corresponding to the value using the determined print sheet.