ChillTest: Esky Ice TestChillTest: Esky Ice Test
Every esky reckons it holds ice for days. Weigh the meltwater and find out what yours really does.
Download on the App StoreFeatures
One number for your esky
Chuck the ice in, leave it a few hours, then weigh the water sitting in the bottom. ChillTest turns that into a single heat-leak figure in watts per degree — a property of the esky itself, not of the day you tested it.
Physics, not a punt
While ice is melting, the inside of an esky sits at 0°C, and melting a kilo of ice takes a fixed 333.55 kJ. Every gram of meltwater is a known amount of heat that leaked in, so this is a measurement rather than a guess.
Kitchen scales and nothing more
No thermometer to buy, no sensor to pair, nothing left rattling around inside. A measuring jug works just as well.
Answers for the trip you are packing
How long 5 kg of ice lasts at 35°C, how much ice a two-night camp needs, whether the pricey rotomoulded esky really doubles the cheap one. Allow for lid opening, sun on the lid and how tightly it is packed.
It will not give you a wrong number
If the ice melted out completely, if ice bricks were used instead of ice, or if it was barely warmer outside than in, the run is not a valid measurement and nothing is shown. You get told what to change instead.
Rank every esky and chilly bin you own
Keep as many as you like, each with its own measurement history, sorted best first. It is your ranking, from your conditions, not a claim off the box.
Every esky is sold on ice-retention days. ChillTest lets you find out what yours actually does — with kitchen scales and a bag of ice.
No thermometer. Nothing to pair. Just meltwater on the scales.
HOW IT WORKS
While ice is melting, the inside of an esky sits at exactly 0°C. That turns the meltwater into a measuring instrument: every gram that melts stands for a known amount of heat that got in. Weigh the water, tell ChillTest how long it sat and how warm it was outside, and the app works out one number for that box — its heat leak, in watts per degree.
That number belongs to the esky itself, not to the day you measured it. Once you have it, ChillTest answers the questions that actually come up:
• How long will 5 kg of ice last at 35°C?
• How much ice do I need for two nights bush camping?
• Is the pricey rotomoulded box really twice the ice box the cheap one is?
NOTHING TO BUY
Kitchen scales or a measuring jug is all you need. No thermometer, no sensors, nothing left sitting inside.
ANY ICE YOU HAVE
Block ice, party ice, cubes, crushed, frozen bottles — set the amount by weight, by volume or by counting pieces. Ice straight from a freezer is below 0°C and lasts a little longer; ChillTest allows for that too.
IT TELLS YOU WHEN A MEASUREMENT DOES NOT COUNT
This is the part most guides skip. If the ice melted away completely, the box never held 0°C and the result means nothing — so ChillTest declines to show a number rather than show a wrong one. Same when the box was not pre-chilled, when the run was too short, or when an ice brick was used instead of ice. Every warning explains what went wrong and what to change.
COMPARE YOUR OWN ESKIES
Keep as many boxes and soft coolers as you like, each with its own measurement history. They sort best first, so the ranking is yours — measured in your conditions, not copied off the sticker.
WHAT YOU GET
• One performance figure per esky, with an estimated range
• Ice-remaining curves for any temperature and any ice load
• Required-ice calculator for a target number of hours
• Adjustments for lid opening, sun and how full the box is
• A step-by-step measuring guide explaining why each step matters
• Metric or imperial, grams or ounces, °C or °F
• Works entirely offline; nothing leaves your device
GOOD FOR
Camping and 4WD touring, caravan trips, fishing and boating, the beach, footy and cricket days, and anyone deciding whether the next esky is worth the money.
These are physical estimates for planning and comparison. Real trips vary with how often the lid is opened, where the box sits and what goes inside. ChillTest measures how quickly ice melts — it is not a food-safety device and does not tell you whether food is safe to eat.