Formula & constants
Application rates scale sharply with pavement temperature: about 2.3 lb per 1,000 sq ft at 30°F, 4.5 lb at 23–28°F, and 6.8 lb or more below 23°F. Rock salt stops melting effectively below roughly 15°F. Pre-wetting with brine cuts usage by up to 30%, and porous asphalt absorbs 20–30% more than smooth concrete. All default values are editable — when your supplier's data sheet or local code says otherwise, use that number.
Where this fits in your project
This tool is one step in a bigger job. Once you have these numbers, salt season budget calculator (Salt Season Budget Calculator), then salt damage & pavement life calculator (Salt Damage & Pavement Life Calculator). For the full sequence see the project workflows, compare approaches on the comparison pages, and check local factors in the state guides.
Frequently asked questions
How much salt do I need per 1,000 square feet?
Roughly 2.3 pounds at a pavement temperature of 30°F after plowing, rising to 4.5 pounds between 23 and 28°F and 6.8 pounds or more below that. Moving from 31°F to 16°F can triple the requirement.
Should I use pavement or air temperature?
Pavement temperature, always. Air temperature can mislead by ten degrees or more, and the pavement is what the deicer actually has to work against.
Does rock salt work in extreme cold?
Not well. Sodium chloride loses practical melting ability below about 15°F. Calcium chloride and magnesium chloride work colder but cost more and are more aggressive to young concrete.
How much does pre-wetting save?
Pre-wetting salt with brine reduces material use by up to 30% with no loss of performance, because wetted salt sticks to the pavement instead of bouncing and scattering.
Can I salt new concrete?
No. Keep new concrete clear of deicing chemicals through its first winter — use sand for traction instead. Chemicals applied too early cause surface scaling that never fully reverses.
Last verified: — See our methodology.
Planning estimates only — confirm quantities with suppliers and local code before ordering.