[Fixed]-Django "DecimalFields must define a 'decimal_places' attribute."


Your max_digits should be greater than the decimal_places

Note that 0.1000000000 uses 10 digits, but 1.0000000000 uses 11 digits. Therefore if you have max_digits=10 and decimal_places=10, then any numbers greater or equal to 1.0 will give errors.

If you don’t need so decimal places, maybe you need something like max_digits=10, decimal_places=3. Or if you really need decimal_places=10, then maybe you need something like max_digits=12, which would support values less that 1000.

Django 1.9 has added a validator to try to prevent errors like this. See ticket 24636 for more details.


Argument max_digits must be greater then decimal_places.


aaf_1kg_all = models.DecimalField(max_digits=5, decimal_places=2, blank=True, null=True)


DECIMAL columns do not permit values larger than the range implied by the column definition. For example, a DECIMAL(3,0) column supports a range of -999 to 999. A DECIMAL(M, D) column permits up to M – D digits to the left of the decimal point.

Mysql Documentation

If you want to accept 10 digits in both number and decimal positions you need to declare ‘aaf_1kg_all’ like this

aaf_1kg_all = models.DecimalField(blank=True, null=True, max_digits=20,  decimal_places=10)

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