Robotic pool cleaner comparison

Dolphin S100 vs Dolphin T15

A side-by-side comparison of pool fit, cleaning coverage, filtration, controls and the better Pool Express option.

By Brian Williamson, Pool Express product specialist
Updated November 9, 2026

Better alternative

A stronger Pool Express option

Dolphin S100 and Dolphin T15 are compared feature by feature below. For a stronger Pool Express option, consider Dolphin Cayman. Inground and above-ground pools up to 40 ft that need floor and wall cleaning.

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S-Line

Dolphin S100

Inground and above-ground pools up to 33 ft that need floor and wall cleaning, with fine debris.

Listed price $849

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T-Line

Dolphin T15

Above-ground pools up to 30 ft that need floor cleaning.

Listed price $649

View better alternatives

A better alternative

What we recommend instead

Pool Express pick

Dolphin Cayman

Inground and above-ground pools up to 40 ft that need floor and wall cleaning.

$1,079

Buy Dolphin Cayman

Buying guidance

Dolphin S100 or Dolphin T15: our take

Dolphin S100 and Dolphin T15 are compared on pool fit, cleaning reach, debris handling, controls and ownership details. The recommendation is based on the job the robot must do—not a simple feature count.

Pool fit and cleaning reach

Dolphin S100 is intended for inground and above-ground pools, while Dolphin T15 is intended for above-ground pools. Dolphin S100 is rated for pools up to 33 ft; Dolphin T15 is rated up to 30 ft. Dolphin S100 cleans floor and walls; Dolphin T15 cleans floor. Dolphin S100's documented cleaning system includes 1 active brush.

Filtration and debris

Dolphin S100 includes Basket and UltraFilter; Dolphin T15 includes Basket. That gives Dolphin S100 the clearer documented edge for fine silt, pollen and sand.

Controls and day-to-day ownership

Dolphin S100 provides a weekly timer and power-supply controls; Dolphin T15 provides one-touch starts and power-supply controls. Dolphin S100 uses a 50 ft corded cable, while Dolphin T15 uses a 40 ft corded cable. Both are listed at 14 lb, so lifting effort is effectively the same.

Price, warranty and the decision

Dolphin S100 is listed at $849 and Dolphin T15 at $649; Dolphin T15 is $200 less. Each lists a 2-year manufacturer warranty. Dolphin S100 and Dolphin T15 each have a specific fit, but neither is the Pool Express pick for this job. Our better alternative is Dolphin Cayman. Inground and above-ground pools up to 40 ft that need floor and wall cleaning.

Feature check: what each robot actually has

A green check means the feature is documented as included. A red X means it is documented as absent. A dash means the source does not make the feature clear.

Feature	Dolphin S100	Dolphin T15
Cleans the pool floor	Yes	Yes
Climbs and cleans walls	YesEdge	No
Scrubs the waterline	No	No
Fine-debris filter included	YesEdge	No
Large-debris filter	Yes	Yes
Automatic scheduling	YesEdge	No
Smartphone app	No	No
Anti-tangle swivel	Not listed	Not listed
3-year warranty	No	No
No recharging between cycles	Yes	Yes
Built-in UV-C water treatment	No	No

Unknown is not treated as “no.” Specifications come from the product pages, current catalog records and manufacturer material collected for this site.

Where Dolphin S100 stands out

Dolphin S100 is the better fit for pools up to 33 ft.

Adds wall climbing and scrubbing
Includes filtration for sand, pollen and other fine debris
Can start on a weekly schedule without a manual launch before every cycle
Is rated for pools up to 33 ft

Where Dolphin T15 stands out

Dolphin T15 is the better fit for shoppers prioritizing the lower $649 starting price.

Is listed $200 lower
Cleans the pool floor