Tool
Compare two products
Pick any two products from our reviews and see specifications, price, buyer ratings and our scores in one table.
Recorded evidence
What separates these listings
- Price snapshot
- $33.00 price gap
- Product B has the lower captured price. This excludes delivery and ongoing costs.
- Editorial assessment
- 0.8-point score gap
- Product A has the higher research score, not a measured performance advantage.
- Specification coverage
- 0 of 16 fields shared
- Shared labels have recorded values on both sides; matching labels do not guarantee matching units or test conditions.
Product A
Sensi Smart Thermostat, Wi-Fi, DIY, Alexa, Energy Star Certified, ST55
- Potential fit
- DIY installers wanting a familiar thermostat design
- Trade-off to resolve
- Outdated aesthetic compared to modern thermostats
Product B
Amazon Smart Thermostat, Save money and energy, Works with Alexa and Ring
- Potential fit
- Alexa-centric homes with verified C-wire setups
- Trade-off to resolve
- Strict C-wire requirement
Side-by-side evidence
16 of 16 recorded specification fields shown
| Side by side |  |  |
|---|---|---|
| Buyer rating | 4.4 | 4.0 |
| Price | $89.99 | $56.99 |
| Our score | 7.6/10 | 6.8/10 |
| Ratings count | 23,162 ratings | 25,666 ratings |
| Brand | Sensi | Amazon |
| Best for | DIY installers wanting a familiar thermostat design | Alexa-centric homes with verified C-wire setups |
| Installation flexibility | 8.8/10 | — |
| Hardware ergonomics | 7.4/10 | — |
| Smart home integration | 8.0/10 | — |
| Energy tracking | 7.6/10 | — |
| Protocol longevity | 6.2/10 | — |
| Hardware engineering | — | 7.5/10 |
| Protocol flexibility | — | 3.0/10 |
| Installation process | — | 6.8/10 |
| Energy efficiency | — | 8.2/10 |
| Market value | — | 8.5/10 |
| Power Source | Battery or C-wire | Not recorded |
| Dimensions | 5.875" x 3.75" x 1.0" | Not recorded |
| Wi-Fi Connectivity | 2.4 GHz | Not recorded |
| Connectivity Technology | Wi-Fi | Not recorded |
| Voltage | 24 volts_of_alternating_current | Not recorded |
| Remote Access | Yes | Not recorded |
| Usage Reports | Yes | Not recorded |
| Energy Star Certified | Yes | Not recorded |
| Smart Alerts | Yes | Not recorded |
| Backlight | Yes | Not recorded |
| Keypad Lockout | Yes | Not recorded |
| Controller Type | Amazon Alexa, Apple HomeKit, Google Assistant, SmartThings, Vera | Not recorded |
| Additional Features | Data Privacy, Easy DIY Install, Energy Savings, Filter Indicator, Programmable | Not recorded |
| Specific Uses For Product | Air Conditioner, Boiler, Furnace, Heat Pump | Not recorded |
| Temperature Control Type | Programmable, Smart/Remote | Not recorded |
| Display Type | LED | Not recorded |
| Our verdict | The Sensi ST55 keeps a traditional thermostat form factor while adding Wi-Fi control and Alexa support for $79.99. It earns a reliable 4.4 rating, often praised for straightforward DIY installation compared to modern puck-style designs. The classic display is utilitarian, avoiding touchscreens in favor of physical buttons. | At $56.99, this is one of the most affordable smart thermostats on the market, built to integrate closely with Alexa and Ring. It explicitly requires a C-wire, meaning older homes without one will face additional adapter costs or complex wiring. The 4.0 rating reflects setup friction and dependence on Amazon's ecosystem. |
| Pros and cons |
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Prices and buyer ratings are captured snapshots. A dash means the detail was not recorded, not that a feature is absent. Editorial scores are research assessments, not laboratory measurements.
Sources and limits
This page summarizes our research reviews of Amazon listings, listed specifications and captured buyer ratings. It is not a hands-on test. Scores are editorial assessments, not measured performance; prices are recorded snapshots and may change. A category can include both main products and accessories, so its overall price range is not the cost of a complete setup.
Most recent product record update: September 25, 2026. Individual records may be older; this is not a verification date for every claim. Prices on this page were read from the listings Nov 12, 2026.
- Amazon listing: Sensi Smart Thermostat, Wi-Fi, DIY, Alexa, Energy Star
- Amazon listing: Amazon Smart Thermostat, Save money and energy, Works
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