Brian Dunning's FileMaker Custom Functions

IsValidTFN ( text )

Validate TFN

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James   James

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  Sample input:
IsValidTFN ( 987654321 )
  Sample output:

  Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

Validates Australian TFN (Tax File Numbers) numbers. The result is either 0 (not valid) or 1 (valid ). Null imput evaluates to 1.

It ignores all spaces and other separators.

This function uses the checksum algortithm as published by the Australian Government.

Currently suitable for 9 digit TFN only.

IsValidABN ( text )



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Note: these functions are not guaranteed or supported by Please contact the individual developer with any questions or problems.

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