Surface Mount LEDs (SMDs)
Surface mount LEDs (SMDs) are flat, leadless emitters designed to solder directly onto a printed circuit board surface. Unlike through-hole DIP LEDs that pass wire leads through holes in a PCB, SMD LEDs sit on top of copper pads and bond during reflow or hand soldering. This surface-mount approach enables dramatically smaller footprints, tighter component spacing, and automated pick-and-place assembly — which is why SMD LEDs dominate commercial LED strips, backlight panels, and virtually every modern electronics product. We stock over 200 individual SMD LEDs across eight package sizes: 0402, 0603, 0805, 1206, PLCC-2 (3528), PLCC-4, PLCC-6 (5050), and 5630/5730. Every color is available — red, orange, amber, yellow, green, blue, white (warm and cool), UV, pink, and RGB — across multiple package sizes so you can match the emitter to your board layout and brightness requirements.
Package size naming follows the imperial dimension convention: the four-digit number represents the length and width of the LED body in hundredths of an inch. An 0402 SMD LED measures 0.04″ × 0.02″ (1.0mm × 0.5mm) — barely visible to the naked eye and ideal for scale modeling, micro-indicator boards, and ultra-compact wearables. An 0603 LED at 1.6mm × 0.8mm is still tiny but much easier to hand-solder with a fine-tip iron and flux. 0805 (2.0mm × 1.25mm) and 1206 (3.2mm × 1.6mm) are the most popular sizes for hobbyist hand-soldering — large enough to work with standard tweezers and a soldering iron, yet small enough to fit dense PCB layouts. The PLCC family uses a different naming convention based on the number of electrical pads: PLCC-2 has two pads (single-color), PLCC-4 has four (RGB common anode or cathode), and PLCC-6 (the 5050 package) has six pads for full RGB control with separate connections to each red, green, and blue die.
Brightness and efficiency vary significantly across SMD packages. Smaller packages (0402, 0603) are limited to roughly 20–50mA and produce modest light output suitable for indicators and accent lighting. Mid-range packages (0805, 1206, PLCC-2) typically run at 20mA and produce several hundred to a few thousand millicandela — bright enough for panel backlighting, signage, and architectural accent applications. The larger PLCC-6 (5050) and 5630/5730 packages push into the 150mA range and deliver substantially higher lumen output, which is why these packages dominate LED strip manufacturing, under-cabinet lighting modules, and commercial signage. The 5630 package, in particular, offers the highest single-emitter brightness in our SMD catalog — several times brighter than a comparable 0805 at the same color. Each product page lists the exact forward voltage, maximum drive current, brightness in millicandela, and viewing angle so you can compare emitters directly.
Soldering SMD LEDs requires different technique than through-hole work, but it is entirely accessible to hobbyists with the right tools. For packages 0805 and larger, a standard fine-tip soldering iron (25–40W), thin solder wire (0.5mm or thinner), liquid or paste flux, and a pair of anti-static tweezers are all you need. Tin one pad with a small solder blob, use tweezers to position the LED, reflow that pad to tack the LED in place, then solder the remaining pad(s). For 0402 and 0603 packages, the process is the same but magnification (a headband loupe or USB microscope) becomes essential — these parts are too small to align with the naked eye. If you would rather skip SMD soldering entirely, our pre-wired SMD LEDs ship with 0402 and 0603 emitters already bonded to fine-gauge magnet wire, ready to glue in place and connect to your power source.
Choosing the right SMD package depends on your application constraints. If board space is the primary concern — wearable electronics, miniature scale models, or high-density indicator arrays — start with 0402 or 0603. If you need a balance between hand-soldering ease and compact size, 0805 and 1206 are the workhorses. If maximum brightness per emitter matters — signage, task lighting, LED strip construction — go with PLCC-6 (5050) or 5630. And if you need full-color mixing from a single emitter, the PLCC-4 and PLCC-6 RGB packages give you independent control over each color channel for PWM color mixing via an Arduino, ESP32, or dedicated LED driver IC.
Like all bare LEDs, SMD emitters require a current-limiting resistor between the power supply and the LED to prevent overcurrent damage. The resistor value depends on your supply voltage, the LED’s forward voltage (Vf), and the desired drive current — use our LED resistor calculator to find the correct value instantly. Forward voltage ranges follow the same pattern as through-hole LEDs: red, orange, yellow, and amber LEDs typically require 2.0–2.2Vf, while blue, green, white, UV, and RGB LEDs need 3.0–3.2Vf. If your power source is AC (landscape transformers) or DCC model railroad track power, you will need a bridge rectifier and smoothing capacitor to convert to clean DC before driving any SMD LED — see the AC/DCC wiring guide for details.
New to LEDs and not sure whether you need SMD or through-hole? If you are building on a breadboard, prototyping without a custom PCB, or need to panel-mount the LED in a bezel or holder, through-hole DIP LEDs are the easier choice. If you are designing a custom PCB, need the smallest possible light source for scale modeling, or want to replicate the emitters used in commercial LED strips and backlights, SMD LEDs are the way to go. Either way, if you want zero-soldering convenience, our pre-wired LEDs come with leads and a resistor already attached — just connect power and ground.