# rounding error with taxes

Hi there,

there seems to be a rounding error with german(?) taxes. Here is what my basket is calculating:

Base Country: Germany

Store Currency: Euro

VAT Tax Rate; 19%

Apply Tax To Shipping Fees? No

Enter Prices Inclusive of Tax? Yes

shopping-cart shows:

T-Shirt 14.00€

Girlie-Shirt 14.00€

Shipping: 5.00€

Taxes: 4.47€

Cart Total: 32.99€

Any ideas how to fix this?

Thanks a lot!

• Kimberly
• Champion of Loops

Matthias,

Thanks for using the WPMU forums :slight_smile:

I’m going to flag the developer on this as I found a similar issue on a wordpress thread and he should already have a fix for this.

Thanks for your patience! We will get this sorted for you.

Best,

Kimberly

• Aaron
• CTO

The numbers look correct here to me when I calculate manually. What’s the problem?

If you were not using inclusive tax pricing, this is what it would equate to:

T-Shirt 11.76€

Girlie-Shirt 11.76€

Shipping: 5.00€

Taxes: 4.47€

Cart Total: 32.99€

As far as the 1 cent rounding issue in that other thread, there isn’t really a way to fix it. It’s a necessary artifact of using inclusive tax pricing and compatibility with gateways which require a rounded line item before tax price that matches the total.

• Matthias Ambre
• New Recruit

Hi there,

thank you for your answer. Well first, its not such easy to tell your customer that he buys 14, 14 and 5 and has to pay 32.99, not 33. Looks like something is wrong. Here in germany normally all prices are inclusive taxes.

I think the problem is, when you mix adding and rounding.

# 1st calculation method:

A_brutto = 14

B_brutto = 14

A_netto = A_brutto/1.19 = 11.7647058823529 ~ 11.76

B_netto = B_brutto/1.19 = 11.7647058823529 ~ 11.76

A_tax = (A_brutto/119)*19 = 2,23529411764707 ~ 2.24

B_tax = (A_brutto/119)*19 = 2,23529411764707 ~ 2.24

SUM_netto = 11,76 + 11,76 = 23,52

SUM_tax = 2.24 + 2.24 = 4.48 (!)

SUM = SUM_netto + SUM_brutto = 28 –> correct

# 2nd calculation method:

SUM = 14 + 14 = 28

SUM_netto = 28/1.19 = 23.5294117647059 ~ 23,53

SUM_tax = (28/119)*19 = 4,47058823529414 ~ 4,47

So, im sorry to disagree. Only if you mix both calculation methods you will get rounding problems…

• Aaron
• CTO

Yes, tax is calculated based on the total. I’m not sure if it will be feasible to calculate it per item for all items.

I’m not sure that it’s that big of a deal? Either method can be off by up to .01 depending on the inputs.

• Matthias Ambre
• New Recruit

Hi there, thank you.

Well i think it isnt a problem if taxes are ±1cent, but i think the total should be the correct addition of the single items.

Well.. i could try to check that myself. Hm… is this the function to have a look at?

``````#marketpress.php line 2038
function tax_price(\$format = false, \$cart = false) {``````

• Matthias Ambre
• New Recruit

PS: germany seems to be a really really complicated country :wink: The biggest problem is, that we have 2 tax rates, depending on the kind of product. So if you sell a Shirt you have 19% taxes inc, if you sell a CD or a book you have 7% tax inc, And on your invoice you need a line for the 7% and one for the 19% taxes included. Well.. I won’t ask you for a feature like this… :slight_smile: