LED Strips

COB LED Strip: How to Choose and Size It

Compare COB strip voltage, output, run limits, cut intervals, CRI, IP ratings and dimming, then calculate load and current for a 24 V installation.

Tomas Reyes · Published September 26, 2026 · 1 Min Read

A COB LED strip is the better choice when you want a smooth, dot-free line, but COB alone does not establish brightness, color quality or compatibility. The compared 24 V RibbonFlex models span 4.5–14.5 W/m, with maximum runs from 10 m down to 6 m as output rises.

Enter the installed length and select an output; the calculator sizes the strip load and checks the run limit.

Size a 24 V RibbonFlex COB Run

Installed length (m)Output tier

Calculated Strip Load

36 WTotal power

1.5 ACurrent at 24 V

8 mMaximum straight run

1Minimum feed sections

The 4 m run is within this model’s 8 m limit. Choose a 24 V constant-voltage driver whose permitted continuous load covers 36 W after any maker-specified derating.

Output	Light output	Max run	Default use
4.5 W/m	165 lm/ft	10 m	Lower output
9 W/m	315 lm/ft	8 m	Medium output
14.5 W/m	442 lm/ft	6 m	Higher output

What COB Changes

LEDVANCE attributes its uniform line with no discernible dots to closely packed chips and a phosphor layer. COB does not itself guarantee a particular voltage, brightness, efficiency, CRI or weather rating.

Cutting, Width and Channel Fit

Published cut intervals include 1.8–2 in for RibbonFlex, 50 mm (2 in) for Solid Apollo and 62.5 mm for LEDVANCE. Published tape widths include 8 mm and 8–10 mm variants. Cut only at marked points and check coating, connector and channel clearance.

CRI and Location Ratings

LEDVANCE lists CRI >90. One Solid Apollo family lists CRI 86+ at 5000 K and 90+ at several warmer color temperatures. The cited location ratings range from RibbonFlex IP20 dry to American Lighting IP54 damp and IP65 wet-location products.

Dimming and Installation Limits

RibbonFlex specifies 0–100% dimming with compatible controls. One American Lighting 24 V product lists TRIAC/ELV dimming from 5–100%. Solid Apollo says not to power its strip while coiled, fold or crease it, or bend it below a 1.5 in diameter. These limits apply to the named products.

Power equals installed length × watts per metre. Current equals power ÷ 24 V. Longer layouts must be divided into manufacturer-approved feeds; reel length is not a straight-run limit.

Sources: RibbonFlex Pro data sheet, LEDVANCE specifications, Solid Apollo data sheet, and American Lighting IP54 and IP65 specifications.

Figures apply only to the cited products. Verify the exact SKU, driver derating, cut marks and location listing before installation. The tool draws on specifications from RibbonFlex Pro, LEDVANCE, Solid Apollo, and American Lighting’s IP54 and IP65 products. See 24V LED power supply: constant voltage or current? and LED strip light channel types and fit.

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