How it Works

  • Most weather apps just tell you if it's sunny. DryOutside.com calculates the Vapor Pressure Deficit (VPD).

    This is the difference between how much moisture the air can hold and how much is currently in it.

    High VPD means your clothes dry in record time; low VPD means they’ll stay damp even if the sun is out.

  • Save Money & The Planet

    • Cost: Running a tumble dryer costs roughly £1.15 per cycle. Line-drying is 100% free.

    • Carbon: Each load dried outside saves approximately 2kg of CO2 from entering the atmosphere.

    • Fabric Care: UV light is a natural disinfectant, and air-drying prevents the heat damage caused by high-temperature dryer drums.

  • Pro Tips for Faster Drying

    1. The Double Spin: Run an extra spin cycle on your washing machine to remove excess water before hanging.

    2. Space it Out: Air needs to circulate. Don't overlap garments on the line.

    3. The Golden Window: Our "Golden Window" forecast identifies the 3-hour period with the lowest humidity—this is your peak drying time.

  • It is the 3-hour period during the day when relative humidity is at its lowest, providing the fastest evaporation rate for your laundry.