💡 CRI & Color Temperature Guide

Understand light quality — no spectral data needed

🌈 Kelvin scale (1000K – 10000K)
🕯️1k🛏️2.7k🍳4k📸5.5k☀️6.5k🔵10k
3000 K Warm white · Cozy
📍 Quick presets
📊 CRI (Ra) Rating Excellent
Poor Fair Good Great Excellent
97 ★★★★★
Typical range: 95–100
💡 Light source
CRI (Ra) range 95–100
R9 (deep red) typical ~95
Color temperature 2700–3000K
Best for Home, photography, retail
ℹ️ About R9 – R9 measures deep red rendering. Many LEDs have low R9, making skin and food look dull. Always check R9 if color accuracy matters.

📘 What is CRI (Color Rendering Index)?

CRI measures how accurately a light source reveals colors compared to natural daylight (Ra = 100). A higher CRI means colors appear more vibrant and true‑to‑life. For homes, CRI 80+ is acceptable; for kitchens, art studios, or photography, aim for CRI 90+. R9 is a special index for deep red — many LEDs score poorly here, affecting skin tones and food appearance.

🔥 Kelvin Color Temperature Guide

2700K – 3000K Warm white · Cozy, relaxing. Ideal for bedrooms, living rooms, restaurants.
3500K – 4000K Neutral white · Clean, focused. Great for kitchens, bathrooms, offices.
5000K – 6500K Cool / Daylight · Energizing, crisp. Perfect for garages, studios, task lighting.
Above 6500K Very cool / Blue‑white · Often used in aquariums or special effects.

❓ Frequently asked questions

What is a good CRI for LED bulbs? For most rooms, CRI 80+ is fine. For makeup, kitchen prep, or artwork, choose CRI 90+.
Why does my LED light make reds look brown? That's low R9. Many standard LEDs have R9 below 20. Look for bulbs that advertise R9 > 50.
Is higher Kelvin always brighter? No. Kelvin describes color appearance (warm vs cool), not brightness (lumens).
Can I use this guide for photography lighting? Absolutely. For accurate color, use lights with CRI ≥95 and a color temperature that matches your environment.

This educational tool uses typical values from industry standards (CIE 13.3, IES TM-30). Actual products may vary; always check manufacturer specs.