MEASURE. CALCULATE. CHOOSE.

LED strip calculators for your next project

Size your power supply, plan controller circuits, estimate room brightness, check feed-cable voltage drop and plan LED strip / housing fit, cuts and parts. Use the specifications for the exact model and colour temperature you plan to buy.

Build a complete project →See wiring diagrams →
5connected planning toolsPower · control · brightness · wire · fit

CALCULATE YOUR LOAD. FIND YOUR POWER SUPPLY.

1. LED strip power supply calculator & selector

Match your LED strip load to real constant-voltage DC power supplies. Start with the maximum power for your exact LED strip model.

A controller's amp rating is its load capacity, not extra power consumption. We use 80% of its total and per-channel current limits.

The location above is for the power supply itself. An outdoor LED strip can use an indoor supply when that supply is installed in a suitable dry location.

How the power supply matching works

LED strip load = metres × W/m
Minimum usable DC output at your conditions = LED strip load ÷ 0.8 (1.25 × load)
Recommended LED strip load = manufacturer-allowed output at those conditions × 0.8
Load utilisation = LED strip watts ÷ allowed DC output watts (not conversion efficiency)
Controller usable current = rated current × 0.8
Controller usable watts = LED strip voltage × usable current

Controller current capacity is not added to the LED strip load. We select a suitable output at or above the actual minimum; there is no additional 10W rounding step. Manufacturer input-voltage and ambient-temperature limits are applied where model-specific evidence is available. Unknown curves or conflicting supplied revisions stay pending; we do not assume that all plastic adapters lose half their output at 110V. Conversion efficiency describes AC input losses and is not subtracted again from a stated DC output rating. Matches must cover both the target watts and target current at the exact DC output voltage, AC input range, installation environment and dimming method. We show reviewed models currently listed with positive stock quantity; price and availability are confirmed on the product page. Assessed candidates appear before pending candidates. Within each evidence group and similar capacity ranges, we prioritize models by units purchased in successful orders over the last 12 months. This is product-family history, not proof that a particular voltage option is the best seller. A supply with a larger series number may have a lower rating at your selected voltage.

Long runs need properly rated wiring and feed points. Do not join the outputs of separate power supplies unless the manufacturer specifically permits parallel operation. Mains connections require a qualified installer.

Browse all power supplies →Read the power calculation guide →

2. LED strip controller capacity & quantity

Choose the connected LED strip type. Analog PWM modes use total and per-channel current limits. Addressable SPI mode calculates pixel capacity and plans independent LED strip power separately.

Use a mode supported by your controller. Equal loading is a planning assumption, not a measurement: RGB colours, white channels and CCT endpoints can draw unequal current. Enter actual highest-channel watts when known. A 5-in-1 controller uses only the channels needed by the selected LED strip type.

Plan LED strip length & controller quantity
Multiple independently controlled zones

Optional. These zone lengths replace the total project length above. Each zone is rounded up separately; controllers are not shared between independent zones. Whole rolls are kept together unless you select cut sections.

We use 80% of both the total and per-channel current rating. The stricter limit decides the usable length. Cut-section quantities must also be checked against the actual LED strip cut interval.

Which LED strip controllers can I check?

This checks electrical loading for analog constant-voltage PWM controllers only. The equal-load option estimates total reference watts divided by the number of active channels and labels the result as an estimate. It does not establish the actual channel current or account for every colour / CCT setting. For verified planning, choose actual highest-channel watts from the LED strip datasheet, including worst-case colour and CCT settings. For a single-colour LED strip, all watts use one channel.

We reserve 20% headroom for this planning check. Voltage and current capacity alone do not prove compatibility: confirm channel count, common-anode/cathode wiring, dimming method and connections. For addressable SPI LED strips, select the pixel mode above; its count estimate still needs model-specific protocol and power-feed checks. DMX universes, DALI addressing, mains and constant-current controllers need separate checks.

Find controller categories →Controller selection guide →

3. LED strip room brightness & length calculator

Start with your room area and target average illuminance. Estimate source lumens, then work out the LED strip length or the lumens per metre your available length must provide.

The filled values are an example, not recommended lighting levels. Select the target for your activity. Replace utilisation, maintenance and diffuser factors with project data. If the quoted lumens already include the diffuser, use transmission = 1.

How we estimate LED strip light output

Required source lumens = area (m²) × lux ÷ (utilisation × maintenance × transmission)
LED strip length = source lumens ÷ LED strip lm/m
Required lm/m = source lumens ÷ available LED strip length

This lumen-method estimate assumes distributed illumination and reports an average. It does not predict shadows, glare, minimum illuminance or uniformity. Cove and other indirect LED strip lighting depend strongly on mounting, room height and surface reflectance. Include existing lighting separately; the result assumes the LED strip supplies the full target.

Use white-channel output for the selected CCT, not combined RGB output. Confirm photometric performance and cut intervals before buying. A plan or light measurement is needed to verify the finished installation.

DOE: lighting quantities and units · ERCO: maintenance factor

Find LED strip options for this brightness →

Send the calculated lm/m target with your chosen CCT, voltage and installation layout. We will check actual model specifications and the matching power supply and controller.

Explore COB LED strip lights →Explore white LED strip options →

DC FEED CABLE — VOLTAGE DROP

4. LED strip wire size & cable length calculator

Find copper conductor sizes in mm² and AWG for the cable from a power supply to a controller or a single-colour LED strip. Enter the load carried by this one cable, not the rating of the power supply.

The selected percentage is a voltage-loss target, not a current rating. A wire can exceed a 3% target while remaining within a 5% target. The length is the distance from supply to load; the calculation includes both outgoing and return conductors.

Advanced: conductor temperature & extra resistance

Default: ideal copper at 20°C, with no extra resistance margin. Increase these values to model a warmer conductor or known extra resistance. These assumptions do not certify current capacity.

What does this cable calculation cover?

Feed current = load watts ÷ DC voltage
Loop resistance = 2 × one-way length × copper resistivity ÷ conductor area
Voltage drop = current × loop resistance

The two-conductor loop is included automatically. It does not calculate the resistance of the LED strip itself, connector losses, mains wiring, or RGB/CCT shared-return conductor loading. For each separate feed, use only the load that feed carries. More voltage allows less current at the same watts, but every device must support that voltage.

Product options use the smaller of the stated metric area and nominal AWG area for this estimate. Stranded and tinned conductors can have different resistance; final sizing should use the cable manufacturer's resistance and current data. Single-core hook-up wire needs two separately insulated conductors for a DC feed; a two-core cable already includes both.

Reference: NIST copper wire tables · UL wire and cable application guide.

Browse wire & cable options →Wire gauge and feed-point guide →Read about voltage drop →

CHOOSE YOUR LED STRIP. FIND WHAT FITS.

5. Find an aluminum channel or neon sleeve

Select your LED strip, choose how you want to install it, then enter the lengths you need. Get matching size candidates, a cut list and a parts list.

1. Which LED strip are you using?

Search our active LED strip catalog. Option dimensions are shown where available; missing or changed specifications are marked for confirmation.

2. How would you like to install it?

Ask us to confirm this combination →

3. What lengths do you need?

Add one row for each different length. For example: 80 centimetres, 3 pieces and 55 centimetres, 2 pieces. Length means the channel / sleeve body, before any end-cap extension.

Each piece is independently fed. The LED strip is rounded down to its cutting unit and the available space. We reuse suitable offcuts when calculating purchase quantities.

Advanced options: connections, stock lengths & cutting allowances
Complete missing product measurements

These are your confirmed measurements / selected purchase options. Enter only values checked for the exact product variant. They do not become manufacturer-reviewed specifications.

Measure finished LED strip height, including chips, coating and adhesive. Housing height means usable space below the installed diffuser, not its outside height.

Missing closed connector measurements

Measure the closed connector body, not its PCB size or wire length. Confirm pin order, current rating and wire exit separately.

Defaults are planning assumptions: 5mm at each end, 20mm for an inside connection, 2mm saw kerf and 0.5m maximum clip spacing. They are not measured manufacturer dimensions. Allow for cable bends and end-cap extensions; follow the actual LED cut marks.

Start by selecting your LED strip in step 1.
How to read the result

Listed size limits passed means the checked width and height fit the selected limits. Measurements / review needed means we can estimate cuts and parts, but a missing height or installation detail still needs confirmation. Does not fit blocks the purchase list for that combination.

Size matching does not confirm the complete electrical, thermal, optical or sealed assembly. Curves need the actual bend plane and minimum radius. Included hardware is credited only when its quantity is documented; unknown quantities stay visible. Mounting clips must match the housing shape, not just the LED PCB width.

The cut plan reuses offcuts with a best-fit heuristic, not a guarantee of minimum waste. A requested piece must fit one stock length. Whole-stock packing targets can increase order quantities; final cart grouping or factory-cut packing may change them. End sealing is counted by ends; sealant cartridges, screws and wiring length are not given invented quantities.

Browse aluminum channels →Browse silicone sleeves →Installation videos →Connection diagrams →

Bring your LED strip calculations into a project

Copy your calculated values for reference, or send them to our team with a drawing. Our team can check the specific LED strip, power supply, controller and feed points together.

Send calculations to our team →Open project builder →

24V driver connection and built-in dimming example