[atopal]

It’s called SSI, spectral similarity index. SSI is specified for a color temperature, eg 3200 or 5600. 100 is identical to tungsten or sunlight. Values above 85 are good.

[yarekt]

In the UK I've not been able to find high wattage (10-20W) LED lightbulbs with high CRI, some don't even mention it in listings, let alone SSI, which I have never seen.

Where are you seeing these? Is this industrial/commercial suppliers?

[atopal]

It’s rare, unfortunately, and usually not in the typical bulb formats. Here’s one for example with an SSI of 89 for tungsten: https://amarancreators.com/products/amaran-100x-s?Title=Defa...

[johanvts]

Phillips, try searching for EyeComfort. I think all of their premium bulbs have 80+ Ra.