Sharp Sharp R-428JK Black Carousel Countertop Microwave review: pros, cons & who it suits

THE SHORT ANSWER

Our take

Sharp R-428JK is a black 1.6-cu.-ft., 1,200-W home-use sensor microwave with 120-V/60-Hz supply and an optional exact black trim kit.

Consider it for

Consider R-428JK if a black 1.6-cu.-ft. sensor microwave and an optional exact black trim route suit your plan. Sharp R-520JW provides a larger 2.0-cu.-ft. cavity with the same listed 1,200-W output and a white kit route. Confirm the exact model, tray fit, kit opening and electrical plan before installation..

Look elsewhere if

Choose another model if you require a verified numeric R-428JK turntable diameter or a bundled trim kit; the tray mapping is unresolved and the kit is documented as optional.

Pros & cons

What could work for you, and what to consider before buying.

What works in its favor

The exact family manual supports a 1.6-cu.-ft. cavity, 1,200-W output, sensor cooking and U.S. 120-V/60-Hz supply.
The K suffix identifies the black variant, with model-specific optional kit RK-46K24.
Sharp classifies this manual family for home use rather than commercial foodservice.

What to weigh up

The two-model turntable figures cannot be assigned confidently to R-428JK in the saved extraction.
A trim kit is separate and requires checking the exact opening and installation instructions.
The historical ASIN is not verified as a current exact offer.

The key details

Published product specifications
Model covered	R-428JK
Capacity	Exact R-428JK black model; K suffix maps to black in Sharp's manual
Microwave output	1.6 cu. ft. capacity and 1,200-W microwave output
Cooking approach	Sensor Cook and Sensor Reheat documented for the shared R-428J family
Installation options	Manual lists 120 V / 60 Hz and home-use classification
Finish and turntable	Optional black RK-46K24 trim kit; exact tray diameter is not assigned

Performance figures are manufacturer claims. Source checked October 11, 2026. Regional models and included accessories can differ.

What the features mean for you

Use the 1.6-cu.-ft. cavity as a size comparison

Sharp's table lists 1.6 cu. ft. for the R-428J family and the exact manual cover includes the R-428JK variant. That places it above compact 0.7- and 0.9-cu.-ft. options, but the capacity figure is not a promise that every dish will fit. The table also shows two tray diameters across R-428J and R-520J models; the saved text extraction does not assign those two numbers safely to the individual columns. Measure your cookware and consult the exact manual rather than treating the R-520J tray figure as an R-428JK specification.

Compare the stated output and sensor functions

The exact family manual lists 1,200 W of microwave output and describes Sensor Cook and Sensor Reheat. Those documented functions distinguish the R-428JK from compact models whose sources list only timed or preset controls. A sensor feature adjusts a cooking cycle based on detected vapor; it is not a guarantee that every food or portion will finish exactly as expected. Sharp's instructions still call for correct preparation and checking food. The 1,200-W value is the stated microwave output and should not be confused with the separate electrical input figure shown in the specification table.

Use the exact supply and household classification

Sharp's specification table lists single-phase 120 V, 60 Hz for the R-428J and R-520J families, and the manual identifies the included J/K/W suffix models. It also describes these appliances as home-use models. That supports the standard U.S. supply path and distinguishes household use from a manufacturer-classified foodservice oven. Still check the exact appliance nameplate, amperage, grounding, circuit and clearance before connecting it. The source lists electrical input separately from 1,200-W cooking output, so use the input/current information for circuit planning rather than treating output as the load.

Treat the optional kit as a separate installation route

The manual names RK-46K24 as the black built-in kit for R-428JK, while RK-46W24 is assigned to the white R-428JW. This is useful if you may want a cabinet or wall installation, but the kit is not shown as included with the oven. Match the exact K suffix and kit, measure the specified opening, and follow the installation instructions and ventilation requirements. A compatible trim route does not mean that any kit in the same R-428 family will fit, nor does it make an unbundled listing a built-in package.

Keep the black R-428J variant exact

Sharp maps the trailing K on R-428JK to black and lists the white R-428JW separately. The model code should remain attached to the black finish and RK-46K24 kit; do not merge it with R-428J listings missing a suffix or borrow the white kit's compatibility. The historical retailer title also calls the unit black, which agrees with the manual suffix mapping. Check the full code on any current seller page and on the unit before ordering parts or a trim accessory. The tagged search uses R-428JK because the old ASIN did not establish a current offer.

Choose between cavity size and exact kit needs

R-428JK suits a buyer seeking a black 1.6-cu.-ft. sensor model with documented supply and a separate black trim option. If you need more interior volume, R-520JW lists 2.0 cu. ft. at the same 1,200-W output class and has its own white trim kits; that changes space and finish rather than microwave output. The tray diameter for R-428JK remains unknown, so a buyer whose dishes must fit a numeric tray should confirm it before selecting. No personal test, reliability claim, current price or buyer-review summary is used.

What else to compare

Amana Amana RMS10DSA 0.8-Cu.-Ft. Commercial Dial-Control Countertop Microwave Commercial 0.8-cu.-ft. countertop model with 1,000-W output and six-minute dial timer. RMS10DSA is a compact, explicitly foodservice-classified countertop microwave with 1,000-W IEC output, stainless interior/exterior, a 12-in. platter and simple dial operation. Its six-minute timer and full-power-only interface distinguish it from touch-programmed commercial models.Mainstay Mainstays EM720CGA-W 0.7-Cu.-Ft. White Countertop Microwave 0.7-cu.-ft. white model with 700-W output and 10-in. turntable. The exact white EM720CGA-W identity is independently tied to B06Y5M61H3, and its family manual provides concrete size and electrical figures: 0.7 cu. ft., 700-W output, 1,050-W input and a 10-in. tray. This supports a tagged direct product link without relying on a title alone.Sharp Sharp SMC1131CB 1.1-Cu.-Ft. Black Countertop Microwave 1.1-cu.-ft. black model with 1,000-W output and 11.2-in. Carousel turntable. SMC1131CB pairs a 1.1-cu.-ft. black countertop body with 1,000-W output and an 11.2-in. tray. Sharp documents ten power levels, simple one-touch controls, auto defrost and express cook, giving the model more usable comparison points than its renewed offer title alone.

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Before you buy

What capacity and output does R-428JK list?

Sharp's R-428J family table lists 1.6 cu. ft. and 1,200 W output.

Does it have sensor cooking?

The shared operation manual describes Sensor Cook and Sensor Reheat.

What does the K suffix mean?

Sharp maps K to black and names the black RK-46K24 trim kit for R-428JK.

Is U.S. supply documented?

The family specification table lists 120 V / 60 Hz; check the exact appliance label and circuit.

What is the turntable diameter?

The saved two-model table extraction does not safely assign either tray diameter to R-428JK.

Is the historical Amazon ASIN current?

That has not been verified; the link searches the exact R-428JK code.

Where can I check the current price?

Use the Amazon link for current offers. Check the exact model, seller, product condition, delivery, and return terms. This page does not display a live price or confirm stock.

Sources & review basis

We use the following manufacturer documentation for the product features above. Our suitability notes and buying advice are editorial judgments based on those features, not measured performance results.

Sharp R-428J/R-520J operation manual ↗ — checked October 11, 2026.
Sharp manual covers R-428JK/JW and R-520JK/JW, maps the K suffix to black, documents Sensor Cook, lists separate R-428J/R-520J capacities and 1,200-W outputs with 120-V/60-Hz supply, identifies home use and names RK-46K24 for R-428JK. ↗ — checked October 11, 2026.
Exact-model index corroborates R-428JK as a home-use Carousel microwave and lists sensor-cook functionality; not used to assign a tray diameter. ↗ — checked October 11, 2026.

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The decision