A lot of light bulb packaging comes with a color measurement (this is reported in Kelvins - K) and a description of the color (warm white, soft white, cool white, etc). According to Wikipedia, most incandescent bulbs fall within the range of 2800 and 3300K. So when you're looking for a CFL that has a similar light, pick a bulb in that range.
Here is a guide from 1000bulbs.com to help you choose a color temperature.
Kelvin Temperature K - What is the perfect color temperature for you?
- 2700k - Homes, restaurants, hotel lobbies, boutiques
- 3000k - Libraries, office areas, retail stores
- 4100k - Showrooms, bookstores, office areas
- 5000k - Museums, jewlery stores, hospitals
- 5600k - Used to simulate outdoor conditions
Bulbs Have Vastly Different Color Temperatures
Many people are familiar with "cool" white or "warm" white incandescent light bulbs. These bulbs have vastly different color temperatures.
The "warm" white light bulb often has a color temperature of up to 2800K. It imparts a more orange/red light on objects. Because you normally associate warmth with red or orange objects, this accounts for the "warm" descriptive name, even though it is a cooler temperature on the Kelvin scale.
Halogen White bulbs fall within the range of 2800K to 3500K. They impart a clear, white light with very little red or blue tones.
A "cool" white bulb commonly has a color temperature of 3600K to 4900K. This is in the low range of blue color, similar to ice. Hence, the "cool" adjective.
Full Spectrum Bulbs have a color temperature of 5000K and above. They impart a bright, white light that makes all colors stand out. Be sure that the bulb you choose for full spectrum applications says “Full Spectrum” as all full spectrum bulbs are 5000K and above but not all 5000K and above bulbs are “Full Spectrum”.
Bulbs that are 5600K and up are considered Daylight bulbs. These bulbs offer a clean, bright light.
Color Temperature Can Affect the Way Things Look in Your House
If you decorate with reds, browns, and oranges, you want to illuminate these rooms with bulbs that have a color temperature in the 2750 - 3000K range. Conversely, if you happen to like green or blue colors, light these rooms with bulbs that produce color temperatures of 4000K or above.
And while full spectrum lighting sounds good in theory, many will find this type of lighting too harsh for overall home lighting applications. It’s best to install full spectrum bulbs in those fixtures that are used when you need to differentiate between colors.
So What is the Perfect Color Temperature for Residential Interiors?
Most people prefer around 2700K - 3000K for a warm, cozy, romantic, and sheltered experience. Fortunately, our CFLs cover all ranges of lighting color temperature needs.
(Source: 1000bulbs.com Color Temperature)