Pool Thermometer

A wireless pool thermometer is a floating waterproof sensor that measures your water temperature and beams it to a small receiver you keep indoors, so you know exactly how warm the pool is without walking outside to check. Set the floater in the water, keep the receiver on the kitchen counter, and one glance tells you whether it's warm enough to swim or whether the heater needs more time. If you own a pool, hot tub, spa, or cold plunge, it saves you the trips outside and helps you run the heater only when you need to, which saves energy too.

Pick by whether you want to read it poolside or from indoors:

• Best-seller, pool + indoor conditions on one screen: the TP211B sends the water temp up to 500 ft to a backlit indoor receiver that also shows your room temperature and humidity, so one glance tells you if it's warm enough to swim and comfortable to sit outside. Adds a pool/hot tub mode, 24-hour and all-time records, and comes in value packs and 2-packs.
• Solar-powered wireless, never change the floater's battery: the TP212 does the same 500-ft indoor monitoring but charges itself in daylight and refreshes every 5 seconds. Shows water temperature only.
• Simplest and most affordable, read it poolside: the TP111 is a solar-powered floater with big fog-resistant dual screens right on the device, refreshing every 5 seconds. No receiver, no pairing, no setup. Drop it in and read it.

Yes! The floating sensor is IPX8 rated for full submersion and ultrasonic-sealed to keep water, fog, and leaks out, so it lives in the water without failing. The shell is high-quality UV-resistant ABS built to handle chlorine, sun, rain, and cold without fading or cracking. Leave it floating all summer, and it just keeps reporting.

With the wireless models, yes, and that's the main reason to choose one. The TP211B and TP212 transmit up to 500 feet to an indoor receiver, so you can check the pool from the kitchen, living room, or bedroom without stepping outside. The TP111 displays only on the floater itself, so you read it at the water's edge, which is perfectly fine if you're heading out to the pool anyway. One honest note on the wireless models: walls, glass, and metal shorten real-world range, so keep the receiver near a window facing the pool for the strongest signal.

Plenty. With a wide -40°F to 158°F range, the same thermometer handles a heated pool, a hot tub or spa, a cold plunge or ice bath, a koi pond, an aquarium, or even a baby's bath. It's especially handy for cold plunge and ice bath fans who need to hit an exact temperature, and the TP211B's pool/hot tub mode gives the right comfort guidance for each. Just note the sensor is built for water, not air, so it's not meant to measure outdoor air temperature.

You choose your power style. The best-selling TP211B runs on standard AAA batteries, simple and reliable. The solar TP212 never needs a battery swap: it has a built-in rechargeable battery that the solar cell tops up in daylight and stores that charge, so it keeps running through cloudy stretches, overnight, and all season long. For best results, let it charge in the sun before first use. The TP111 is the simplest floating option, reading right on the device with no receiver. Most owners pick the TP211B for its dual pool-and-indoor display; go with the TP212 if maintenance-free, set-it-and-forget-it power is your top priority.

All three are accurate to ±0.9°F across the full range. The TP211B uniquely shows your water temperature next to indoor room temperature and humidity on the same receiver, giving you the full picture at a glance, and keeps 24-hour and all-time high/low records. The TP212 and TP111 focus purely on water temperature and refresh it every 5 seconds for near real-time readings, with the TP111's big dual screens readable from several feet away.

Every TempPro pool thermometer, the TP211B, TP212, and TP111, reads to ±0.9°F (±0.5°C) across a wide -40°F to 158°F range, tight enough to trust for a comfortable swim, a precise cold plunge, or a baby-safe bath. There's no calibration to do: each one is factory-calibrated and ready to read straight out of the water, with no dials to set and no drift to correct over time, which is a common headache with cheap analog floaters that slowly read high or low. If you ever want to sanity-check it, drop it in a glass of ice water and it should read close to 32°F. Just give the sensor a minute or two to fully settle to the water temperature before trusting the number.

Not if you tether it. Every TempPro pool thermometer includes a rope, so you can tie the floater to a ladder, railing, or any fixed point to keep it from drifting into the skimmer or across the pool. This also gives a truer reading, since water inside a skimmer circulates differently. For the most accurate temperature, anchor it in an open area with good water flow, ideally near a return jet.

It comes down to convenience. A basic floating thermometer works, but you have to walk out to the pool and fish it out to read it every single time. A wireless model like the TP211B sends the reading straight to a screen inside your home, so you check it in a second, decide whether to swim, and run the heater only when it actually pays off. For anyone who checks their water regularly or heats their pool, the trips and the energy you save quickly make the wireless version worth it.

TempPro (formerly ThermoPro) has sold millions of thermometers and is trusted for accurate, affordable monitoring. Our wireless pool thermometers pair an IPX8 fully waterproof floating sensor with a 500-ft range, ±0.9°F accuracy, and a backlit indoor receiver, with no app required, and the best-selling TP211B uniquely shows pool and indoor conditions on the same screen. Order direct and you also get a 30-day money-back guarantee, free shipping over $30, lifetime customer support, and value-pack bundle deals you won't find on marketplaces.