Fast Food Calorie Calculator

How it works

Large fast food and quick service chains in Australia are legally required to display the energy content of each menu item in kilojoules, on menu boards, digital screens and websites, under the kilojoule labelling requirements in the Food Standards Code. That’s why you’ll see a small “kJ” figure printed next to the price of every burger, burrito, box or drink at chains like Guzman y Gomez, McDonald’s, KFC and Subway.

This calculator doesn’t know what any specific menu item costs in energy — menus change too often for a fixed list to stay accurate — so instead it does the one job that’s actually useful once you’re standing at the board: add up the kJ figures you read off it, for as many items as you’re ordering, and convert the total into calories and a percentage of a daily reference figure.

Total kJ = sum of every item's kJ figure
Total calories = Total kJ ÷ 4.184
% of daily intake = (Total kJ ÷ 8,700) × 100

8,700kJ is the average adult daily energy intake reference set by the Food Standards Code — it’s the exact figure Australian menu boards are required to print (usually as a line like “the average adult daily energy intake is 8,700kJ”) so shoppers have a consistent benchmark to measure any single item or order against. It’s specifically an Australian regulatory figure, not a universal medical recommendation — see the FAQ below for how it can differ from your own needs.

4.184kJ per calorie is the standard scientific conversion between the two energy units, and it’s constant everywhere — 1 calorie is defined as exactly 4.184 kilojoules, regardless of what’s being measured. That part of this calculator works the same for a menu board in Sydney, London or anywhere else that lists kilojoules.

Worked example

Aisha is grabbing lunch from a Guzman y Gomez in Melbourne’s CBD. The store’s digital menu board lists a kJ figure next to every item, so as she orders she reads off three numbers: her burrito, a side of chips, and a soft drink.

(The figures below are illustrative — a plausible set of numbers a customer might read off a board on any given day — not sourced GYG menu data. Real menu items and their kJ values change over time, so always use the live figure shown on the actual board or website when you order.)

Item	kJ (read from the board)
Burrito	2,510
Chips	1,180
Soft drink	860

Adding the three figures gives her order’s total energy:

2,510 + 1,180 + 860 = 4,550 kJ

Converting that to calories:

4,550 ÷ 4.184 ≈ 1,087 calories

And as a share of the 8,700kJ average daily reference printed on the board:

(4,550 ÷ 8,700) × 100 ≈ 52.3%

So Aisha’s order comes to just over half of the average adult’s daily energy reference in one sitting — useful context for deciding whether to also order a side, or save some of it for later, without needing to know any exact published nutrition data for the store.