The free online GST and GST Free Portion Calculator! Provided here for your use. Please make sure you report any issues with the calculator in the comments below. Enjoy your calculations!
I wrote this simple little script in JavaScript to help me calculate Australian GST (10%) today. Being such a useful little script, I thought I would post it.
Please feel free to use this script as your require, if you wish to have this script on your own website please post an acknowledgement and link back to this page.
How to Calculate GST the hard way (using you know, numbers and shit)
If you have something without GST, and you need it with GST, you add 10%. Which is easilest done on a calculator by multiplying your amount by 1.1 (which is really saying mister Calculator, give me 110% of this amount).
$100 * 1.1 = $110
To go the other way, let's say we have $110, which includes 10% GST already. Working out how much is the GST part is quickly done on a calculator by dividing by 11. Not 10 you say? No, 11. Because easiestly explained, before GST you had 10 parts of a number, the "extra" 10% is another "part". So we need to work out what that part is.
$110 / 11 = $10
Huzzah! We have the GST component of an amount! Now, we need to take that GST part from our original amount of $110 to get what the amount is without GST.
$110 - $10 = $100
Perfect :-)
But seriously, why do all this manual work when this GST calculator does it for you?
Last Updated 04/03/2014: Fixed floating point arithmetic (Loss of 1c on some calculations). Thanks to Michael for pointing it out.
Hi … great tool however i’m having a small problem with calculating non-gst amounts. Everytime i put in the total amount and the gst stated amount (both have cents in them) i keep getting “Unable to Calculate”. i’ve read through the comments and made sure there are no $ in the amounts so not sure what’s going on.
As i said – awesome tool – has helped a lot especially at work.
Cheers
What amounts are you using?
1038.58 total and 94.42 gst stated
Using the GST calculator – $1038.58 including GST breaks down to $944.16 including $94.42 GST.
So there is no GST-free (or shouldn’t be) based on that amount.
Instead of the program reporting $0 GST-free – there’d be some number smaller 1c defined as GST-Free. But that’s why it says it can’t calculate it.
If you have $110, the maximum amount of GST that can be in that amount – is $10. If you state something over that, it won’t be able to calculate any portion of that as GST-free.
So if the Total is $110, any amount of GST stated “less” than $10, will give you the GST-free portion.
If you state $10 as GST there’ll be $0 as GST-free.
Hope this maybe points you in the right direction.
Once again your page has saved my day….. thanks for a lifesaver of a page …..Thankyou, Thankyou, Thankyou
this is a great tool and has helped me heaps thks alot a brilliant idea
Love this calculator, I use it almost every day. GENIUS.
thanks a million i use your calculator all day long it makes a life a lot easier!!!!!!!!!!!!!!
Really confused now. How do I calculate GST free amount in the updated calculator?
Hasn’t changed. If you have the following amounts:
Total $110
Gst Stated: $10
GST-Free Portion = $0
GST-Component of the total amount = $110 (which is split in $100 gst-taxable. $10 GST Amount)
Total $110
GST Stated: $5
GST-Free Portion = $55
GST-Component of total amount = $55 (which is split as $50 gst-taxable. $5 gst amount).
All the new portion is doing is showing the amount break down for the GST part.
Thanks – did not do that this morning. When I entered total and GST stated, it said it could not calculate. Great calculator by the way.
Careful when you copy/paste into the calculator – if the calculator sees $ now, it can’t calculate it (because $ isn’t a number).
“Used” to say NaN (or Not a Number) – but I’m slowing putting in nice error messages. (Slowly).
Hi Dazz,
In the old script could put in the GST Stated: eg 10 and it would work backwards eg give you -$110.00 in GST Free Amount:. Eg you know the GST amount but don’t know the sale price. Not man would use it I guess 🙂
Cheers
Tim
Thank you thank you! What a brilliant idea!
Great site mate, had to use it for a business course in TAFE and you save a bucket load of time.. Now I have extra time to surf the endless sites provided by that thing called the internet 🙂 (apparently there is more then porn on the net) lol
Thank you soooooo much 🙂 It is really helpful ^^. Could you please let me know how to calculate it in the calculator? In the exam I cannot use laptop and open your page.
To add GST – you simply times your amount by 1.1. $100 * 1.1 = $110 inc gst.
To caclulate GST, divide by 11. $110 / 11 = $10 GST.
Take the calculated GST ($10) from the original amount ($110) to discover what something is without GST – $110 – $10 = $100 ex. gst
Oh thanks a million. You have made my life sooooo much better. Thank God for Miracles….
LOL :))
This is an awesome page. Very very helpful for my studies. Please consider making an app…
Brilliant. What a lifesaver this has turned out to be on the day. A Big thankyou for your efforts!
What a fantastic GST calculator, you just made my life easier.
Thankyou so much !!! So glad I came across this site it has definitely been a god sent and has made my life a little less complicated so again thankyou xx
Hi There!
This is such an excellent website. I am currently collating thousands of receipts and it just makes my life so much easier. Thank you so much for your help.
ever thought of a smart phone ‘app’ for this?
Several times. Haven’t really had the time to muck about with it though. I’ll get there.
Hoo-rah!
lol well HI there.
Thanks for this, you are legendary.
Your a legend. !!!
Absolutely wonderful. It has saved me heaps of time, and its made it soooo easy. Job well done
love your work, it is fantastic.
you made people life easy for them
i really appreciate you work.
thanks a million
Yeah, this is great.
One of the most useful tools on the internet.
Seriously. Thanks a bunch.
This page has been so helpful for me! thankyou very very much!!!
Just found this – thanks Darren, makes things easy for a maths clutz.