Spa Calc
English

Comparison

Spa Calc vs the Intex Hot Tub App (INTEX Link)

INTEX Link is Intex's app for PureSpa models with the Wi-Fi icon: set the temperature, program the heater, keep an idle temperature and schedule filtration, plus scheduled chlorination on select models. It's a remote for the tub. Spa Calc is for the water: whether it's safe to soak, what to add and when to drain. Most PureSpa owners with a Wi-Fi model would use both.

Prices, features and ratings checked on 28 October 2026.
App Store rating as shown on 28 October 2026: 2.2 stars from 17 ratings on the US App Store.

The short answer

INTEX Link runs the tub; Spa Calc looks after the water. Keep INTEX Link for the heater and schedules if you have a Wi-Fi PureSpa, and use Spa Calc for the soak check, the doses and the drain date.

At a glance

From each app's own App Store page and website, checked on 28 October 2026. "Not listed" means we found no mention of it there, not that the feature is missing.
FeatureSpa CalcINTEX Link
Price Free for one tub Free
Heater and temperature control No Yes
Filtration schedule No Yes
Scheduled chlorination No Yes Select models
Needs compatible hardware No, works with any tub Yes, Wi-Fi PureSpa models
Connection None Bluetooth or 2.4 GHz Wi-Fi
"Ready to soak?" check Yes Not listed
Chemical doses Yes Teaspoons, grams or your own scoop Not listed
Inflatable size presets Yes Not applicable
Salt water tubs Yes Salt mode Not listed
Bromine Yes Not listed
Drain and refill countdown Yes Not listed
Filter care reminders Yes Shorter defaults for inflatables Maintenance scheduling
Test log and charts Yes Not listed
Languages English 62 languages listed
Account to sign up for None Not listed ; email, phone and user ID listed as linked data

Pricing

Our app

Spa Calc

  • Free$0Every feature for one tub, inflatables included.
  • Plus$1.99 a month, $14.99 a year or $39.99 onceUp to 10 tubs plus the host and pro tools. 1-week free trial on the yearly plan.
  • Pro$9.99 a month or $79.99 a yearUnlimited tubs plus the host and pro tools. 1-month free trial on the yearly plan.

Prices on the App Store at launch. Pricing is per person, not per tub.

Inflatable hot tub controller

INTEX Link

  • INTEX LinkFreeHeater and temperature, idle temperature, scheduled maintenance and, on select models, scheduled chlorination with filtration.

Free on the App Store. Works with Intex PureSpa models that show the Wi-Fi icon.

Prices as listed on 28 October 2026. Source

Both are free for one tub. INTEX Link comes with the hardware. Spa Calc is paid only for more than one tub, for rental hosts and service techs.

Soak check, then soak

Spa Calc's first screen says whether the tub is ready. Enter sanitizer and pH and it says ready, what to add first, or how long to wait after a shock. After you get out, "I just soaked" logs how many people were in and for how long and gives a top-up dose.

Teaspoon doses for a small tub

Inflatables hold a few hundred gallons, so a small mistake is a big change. Spa Calc gives doses in teaspoons down to an eighth, or grams, for the product and strength on your shelf. Pick your tub from the inflatable presets or type the volume, then confirm it at your fill line.

Nothing to pair, nothing to drop

Spa Calc doesn't connect to the tub, so there's no pairing, no network setup and nothing to re-add after a reset.

What INTEX Link Users Complain About

Paraphrased from public reviews. Each one links to where it was posted and gives the month it was written.

  • The tub drops off the app. A July 2024 reviewer said the spa had to be added to the app again after every device reset (App Store review, July 2024).

    Spa Calc approach: Spa Calc stores your tub in the app and your iCloud, not on a connection. It stays put.

  • Schedules that don't run. An August 2024 reviewer said scheduled sanitation sometimes failed or started at the wrong time and the app and spa sometimes stopped talking (App Store review, August 2024).

    Spa Calc approach: Spa Calc can't run the chlorinator, but it can tell you what the water needs from your test, and reminds you to test on the schedule you choose.

  • A blank screen. A March 2025 reviewer said the app's screen goes white daily and needs a phone restart (App Store review, March 2025).

    Spa Calc approach: a native iPhone app with no connection to wait on.

  • You want to heat the tub remotely, set an idle temperature or change the filter schedule from your phone. Spa Calc doesn't control hardware.
  • You have one of the select models that can schedule chlorination with filtration.
  • You want the app in a language other than English.

Questions people ask

What is the Intex hot tub app called?

INTEX Link. Its App Store listing says it works with Intex PureSpa models that show the Wi-Fi icon, over Bluetooth or 2.4 GHz Wi-Fi.

Does the Intex app tell me how much chlorine to add?

Its App Store description covers heating, scheduling and, on select models, scheduled chlorination with filtration. It doesn't describe testing the water or chemical doses (checked 28 October 2026). Spa Calc does both, with doses in teaspoons sized for inflatables.

Do I need the INTEX Link app for my PureSpa?

Only to control a Wi-Fi model from your phone. The tub runs from its own control panel. Spa Calc doesn't connect to the tub at all, so it works with any PureSpa.

More comparisons

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References

  1. INTEX Link on the US App Store (rating, description, connectivity, languages, reviews: Jul 2024, Aug 2024, Mar 2025), checked 2026-10-28

Intex, INTEX Link and PureSpa are trademarks of their respective owners. Spa Calc is not affiliated with them. Information checked on 28 October 2026; prices and features change. Corrections: [email protected]