Voltage Drop Chart 12V and 24V

VOLTAGE DROP CHART 12V AND 24V

When current runs through a wire, part of the voltage is lost along the way. That loss is called voltage drop. On an LED strip you see it right away: the first feet are at full brightness, the far end is dimmer or shifts yellow.

The rule is simple: voltage drop = wire resistance × current (E = IR). The longer and thinner the wire, the bigger the loss. The charts below give you, for each power draw and each wire gauge, the maximum run in feet before you exceed a 10 % loss.

How to read the charts

Find the total power you are feeding (the strip's watts per foot × its length).
Pick that row — when you fall between two rows, always take the one above.
Read the distance under the wire gauge you plan to use. That is the maximum length of the pair of wires, from the power supply to the strip.

The dark green columns are the gauges we keep in stock. If the distance shown is shorter than what you need, you have three options: a thicker wire, a power supply closer to the strip, or feeding the strip from both ends.

12 volts — maximum run in feet

Power	Current	8 AWG	10 AWG	12 AWG	14 AWG	16 AWG	18 AWG	20 AWG	22 AWG	24 AWG	26 AWG
3 W	0,25 A	3733	2396	1508	947	595	376	234	146	93	59
4 W	0,33 A	2828	1815	1142	717	451	285	177	111	70	44
5 W	0,42 A	2222	1426	898	564	354	224	139	87	55	35
10 W	0,83 A	1124	722	454	285	179	113	71	44	28	18
20 W	1,67 A	559	359	226	142	89	56	35	22	14	9
30 W	2,50 A	373	240	151	95	60	38	23	15	too short	too short
40 W	3,33 A	280	180	113	71	45	28	18	11	too short	too short
50 W	4,17 A	224	144	90	57	36	23	14	too short	too short	too short
60 W	5,00 A	187	120	75	47	30	19	12	too short	too short	too short
70 W	5,83 A	160	103	65	41	26	16	10	too short	too short	too short
80 W	6,67 A	140	90	57	36	22	14	too short	too short	too short	too short
90 W	7,50 A	124	80	50	32	20	13	too short	too short	too short	too short
100 W	8,33 A	112	72	45	28	18	11	too short	too short	too short	too short
110 W	9,17 A	102	65	41	26	16	10	too short	too short	too short	too short
120 W	10,0 A	93	60	38	24	15	too short	too short	too short	too short	too short

24 volts — maximum run in feet

At the same wattage, 24 V draws half the current of 12 V, so you can run roughly twice as far on the same wire. That is the main reason to pick 24 V on a long run.

Power	Current	8 AWG	10 AWG	12 AWG	14 AWG	16 AWG	18 AWG	20 AWG	22 AWG	24 AWG	26 AWG
3 W	0,13 A	14417	9253	5823	3656	2299	1451	905	565	358	226
4 W	0,17 A	11025	7076	4453	2796	1758	1110	692	432	274	173
5 W	0,21 A	8925	5728	3605	2263	1423	898	560	350	222	140
10 W	0,42 A	4463	2864	1803	1131	712	449	280	175	111	70
20 W	0,83 A	2258	1449	912	573	360	227	142	89	56	35
30 W	1,25 A	1499	962	606	380	239	151	94	59	37	24
40 W	1,67 A	1122	720	453	285	179	113	70	44	28	18
50 W	2,08 A	901	578	364	229	144	91	57	35	22	14
60 W	2,50 A	750	481	303	190	120	75	47	29	19	12
70 W	2,92 A	642	412	259	163	102	65	40	25	16	10
80 W	3,33 A	563	361	227	143	90	57	35	22	14	9
90 W	3,75 A	500	321	202	127	80	50	31	20	12	8
100 W	4,17 A	449	288	182	114	72	45	28	18	11	7
110 W	4,58 A	409	263	165	104	65	41	26	16	10	6
120 W	5,00 A	375	241	151	95	60	38	24	15	9	6
130 W	5,42 A	346	222	140	88	55	35	22	14	9	5
140 W	5,83 A	321	206	130	82	51	32	20	13	8	5
150 W	6,25 A	300	192	121	76	48	30	19	12	7	5
160 W	6,67 A	281	180	114	71	45	28	18	11	7	4
170 W	7,08 A	265	170	107	67	42	27	17	10	7	4
180 W	7,50 A	250	160	101	63	40	25	16	10	6	4
190 W	7,92 A	237	152	96	60	38	24	15	9	6	4
200 W	8,33 A	225	144	91	57	36	23	14	9	6	4

The chart as a PDF

The same two pages, to print or keep on the job site.

Download the chart (PDF)

The wire and power supplies we stock

22-2 black and red wire — for short runs
18-2 outdoor landscaping wire (100 ft)
22-4 wire for RGB strip · 22-5 wire for RGBW strip

The fine print

The charts assume a 10 % loss over the pair of wires. A 20 % loss would double the distance, 5 % would cut it in half.
They assume wire at 70 °F. At 130 °F, expect roughly 3 % more drop.
Minimum operating voltage is assumed at 10 V for 12 V systems, 21.6 V for 24 V systems.
If the manufacturer specifies its own wire gauges, follow those instead of this chart.

Not sure about your project? Write to us or call 450 444-4007 — we will size the installation with you.