Well Sounder icon

How far down is the water in your well?

47.3 ftto water, below ground · ±0.9 ftHigh confidence

Lay your iPhone on the well cap and tap the casing with a rubber mallet. Each tap sends a pulse of sound down the casing; the water sends it back. Well Sounder times the echo and turns it into the depth to water, on your phone, in under a minute.

Coming soon to the App Store

For iPhone and iPad · Drilled wells with 2–8 inch casing · Works offline

🔨 No tape down the well

Nothing goes into the casing. In Tap mode the cap stays on: the phone lies on top, you tap the steel or PVC with a mallet, and it listens.

📈 An echogram, not a guess

See every echo the well sends back, with the water marked. Its double echo (sound bouncing water → cap → water) confirms the pick, and the confidence says how clean the reading was.

🌵 Track a dry season

Save each reading to the well's history and watch the water level through a drought, before the tap starts to sputter.

⏱ Recovery test

After heavy use, take a reading every couple of minutes. Well Sounder charts how fast the water climbs back and estimates the refill rate and yield.

📄 Well report

A one-page PDF with your well's readings, history and recovery test, for a buyer, a seller's disclosure or your pump installer.

🔒 Private

The sound is analysed on your iPhone. No account, no ads, no tracking, and it works with no signal at the well.

How it works

  1. Add your well once. Casing size (usually 4 or 6 inches) and how far it sticks up above the ground.
  2. Let the water settle. Don't run water for about 30 minutes, so you measure the resting (static) level.
  3. Tap. Lay the phone flat on the cap and tap the casing near the top about once a second, 12 times. The app stops by itself.
  4. Read. Depth to water below the top of the casing and below ground, with a ± range and a confidence. Save it to the well's history.

Sound travels down the casing at about 1,120 feet per second, a little faster in warm air, so the app asks for the air temperature in the well and estimates it from your location. Prefer not to tap? Sweep mode plays short tones from the phone's speaker at the vent instead.

What it measures, and what it doesn't. Well Sounder measures the depth to the water: sound reflects off the water surface and can't travel on through it. The total depth of the well (where the drilling stopped) comes from your well log. If you enter it, the app estimates how much water is standing in the casing. It's built for drilled wells with 2–8 inch casing; large dug or bored wells aren't supported yet.

Why it matters

Want to compare every way to measure a well, including the ones that don't need an app? Read how to measure the water level in your well.

Pricing

Your first soundings on one well are free, in full: depth, echogram and confidence. The demo well is always free. Well Sounder Pro adds unlimited soundings, every well, the full history, the recovery test and the well report: $3.99 a month, or $24.99 a year with a 7-day free trial.