LED Sizes Explained: Complete LED Size Chart, Types, Dimensions, and Applications

LEDs come in multiple package types, and choosing the wrong LED size affects brightness, PCB footprint, thermal performance, and assembly method. Whether you are placing an indicator on a breadboard, designing an LED strip PCB, or specifying a COB module for a spotlight, size is the first decision to get right.

This guide covers every major LED size category, through-hole dimensions, SMD package codes, COB module sizes, and the difference between chip size and package size, with a quick-reference chart for each.

Figure: Showing LED package size progression from 0402 SMD chip through 5050 RGB, 5mm through-hole, and 30mm COB module.

LED Sizes Overview

Quick answer: LED sizes fall into four categories based on package type.

• Through-hole: 3mm, 5mm, 8mm, 10mm, identified by body diameter
• SMD indicators: 0402, 0603, 0805, 1206, footprint encoded in part number (mm)
• SMD lighting: 2835, 3528, 5050, 5630 (for example, 2835 = 2.8 x 3.5 mm)
• COB: 10 to 50+ mm modules, sized by light-emitting surface (LES) diameter

SMD LED Sizes

SMD LED package codes encode physical dimensions in millimeters. A 2835 is 2.8 x 3.5 mm; a 5050 is 5.0 x 5.0 mm. Two functional tiers: indicator-class for status LEDs and lighting-class for illumination.

Both types support automated PCB assembly via pick-and-place and reflow soldering. Once an SMD LED is selected, the next step is confirming orientation, which is where this SMD LED polarity guide comes in handy for reading cathode markings and footprint indicators across all package sizes.

SMD LED Size Chart

Footprint dimensions feed directly into your solder pad design, so always confirm pad geometry against the manufacturer's datasheet.

Note: Dimensions are nominal. Always verify pad layout and Vf against the component datasheet before finalizing your PCB footprint.

Figure: SMD LED package scale comparison showing eight packages from 0402 to 5630

Figure: 2835 SMD LED showing top-view dimensions (2.8 x 3.5mm body, 0.9 x 1.4mm pads) and side cross-section with 0.7mm total height, die, and encapsulant.

Most Common SMD LED Packages

0603 LEDs

• 1.6 x 0.8 mm; 0.45 mm tall
• Best for PCB status indicators on compact boards
• Requires automated pick-and-place; not reliably hand-solderable

2835 LEDs

• 2.8 x 3.5 mm; best lumens-per-watt of any mainstream SMD package
• Slim 0.70 mm profile suits LED strips and panel lights
• Standard in modern LED PCB manufacturing, available through JLCPCB's parts library and supported by JLCPCB's PCB assembly service

3528 LEDs

• 3.5 x 2.8 mm; older standard still found in budget decorative strips
• Lower efficiency than 2835; not recommended for new designs

5050 LEDs

• 5.0 x 5.0 mm; three-die package enables RGB color-mixing in a single component
• Standard for addressable strips (WS2812B, SK6812) and architectural color lighting

Through-Hole LED Sizes

Through-hole LEDs are sized by body diameter. Lead pitch is 2.54 mm (100 mil) across all standard sizes. The longer lead is the anode.

Figure: Through-hole LED showing 5mm LED with key dimensions labeled, and size lineup showing 3mm through 10mm LEDs to scale with ruler.

SMD vs Through-Hole LEDs

For a deeper comparison of the two mounting methods beyond LEDs alone, see this guide on surface-mount vs through-hole assembly.

COB LED Sizes

A COB (Chip-on-Board) LED bonds multiple dies directly onto a substrate under a uniform phosphor layer. COBs are sized by LES (Light-Emitting Surface) diameter, not a footprint code.

Key points:

• COB LES size varies by manufacturer; no universal naming standard
• Require a dedicated heatsink and thermal interface material
• Not assembled on FR4 PCBs; distinct from SMD workflows

Figure: COB LED module with red dimension arrow labeling 30mm LES diameter

LED Chip Size vs LED Package Size

The package size is the outer housing: lead frame, lens, encapsulant, and PCB pads. It is what part numbers like 0603, 2835, and 5050 describe.

Chip (die) size is the internal semiconductor die. Standard LEDs typically have a 250 to 500 µm die inside any given package.

Two LEDs with the same package code can have different die sizes, affecting efficiency, flux output, and color consistency. Package size reflects footprint. Die quality reflects performance.

Mini LED and Micro LED Sizes

Mini LED and Micro LED are emerging package categories driven by display technology.

• Mini LED: die size typically below 200 µm; used in backlighting for LCD TVs and monitors with local dimming zones
• Micro LED: die size below 100 µm; used in AR/VR headsets, smartwatches, and high-resolution direct-view displays

Neither type follows standard SMD package naming; sizes are defined by pixel pitch (sub-1 mm) and die transfer method rather than a footprint code

These differ from standard SMD and COB LEDs in the manufacturing process and are not sourced from conventional parts libraries.

2835 vs 3528 vs 5050 SMD LED Comparison

Figure: 5050 SMD LED internal layout diagram showing red, green, and blue dies inside a 5.0 x 5.0mm package with four corner solder pads and dimension labels.

How to Choose the Right LED Size

Check the LED selection quick-reference table

LED Assembly method

• Hand soldering: 5mm THT, 0805, 1206
• Low-volume SMT: 0805, 1206, 2835
• High-volume production: any standardized SMD package

Thermal requirements

• Low-power indicators (0402 to 1206): standard FR4, no extra treatment needed
• Mid-power (2835, 5050): copper pours beneath thermal pad; add thermal vias for better transfer
• High-power (5630, 3030, COB): aluminum-core PCB (MCPCB) or dedicated heatsink required

Figure: Populated PCB showing three LED package zones: 0603 indicators near a microcontroller, a 2835 linear strip array, and a 5050 RGB LED cluster in the corner.

Why LED Size Matters

An LED size refers to the physical dimensions of the LED package, measured either by body diameter (for through-hole LEDs) or by footprint code in millimeters (for SMD LEDs like 2835 or 5050). The size determines how the LED is mounted, how much light it can produce, and how it integrates into a PCB design.

LED size is not just a matter of footprint. It directly affects how your design performs and how it gets built.

• Brightness: Larger packages typically support higher drive currents and higher lumen output
• PCB space: Package footprint determines how many LEDs fit on a board and how dense your layout can get
• Thermal performance: Higher-power packages need copper pours, thermal vias, or an aluminum-core PCB (MCPCB) to stay within the rated junction temperature
• Viewing angle: Through-hole packages focus light tightly (15 to 60 degrees); SMD packages spread it wide (120 to 160 degrees)
• Assembly method: Sub-0805 packages cannot be reliably hand-soldered and require automated pick-and-place equipment
• Cost: Smaller indicator packages are cheaper per unit at volume; high-power packages cost more and require more elaborate PCB substrates

Getting the size right at the design stage avoids the most common LED-related rework: insufficient brightness, overheating, or assembly failures on tight pitches.

FAQs on LED Sizes

Conclusion

LED size selection comes down to board space, brightness, assembly method, and thermal needs. The 5mm through-hole and 2835 SMD cover the majority of common builds. For RGB use 5050; for high-output illumination use COB or 5630/5730.