What's the Difference between T10 and T15?

If you want to upgrade your license plate light, map light, or 3rd brake light, etc to have a completely new experience with LED, you may have come across two frequently encountered bulb models - T10 and T15 - while browsing LED car lights on various shopping websites. If you are unsure about the differences between T10 and T15 and don't know how to choose the right LED bulbs, don't miss out on this article!

Names and common installation positions

T10 is the designation for LED lights, while the original halogen bulbs are typically referred to as W5W (indicating a 5-watt halogen bulb), 194, or 168. They also go by several other names, including 161, 192, 193, 579, and so on. T10 bulbs can be used for both interior and exterior lighting in vehicles. Common interior applications include dome lights, map lights, and trunk lights. For exterior lighting, T10 bulbs are frequently used as license plate lights, side marker lights, and inner tail lights.

T15 is another designation for LED lights, while the original halogen bulbs are generally known as W16W, 921, or 912. These can also be referred to as 904, 906, 916, 917, 920, 922, and so on. T15 bulbs are commonly used as backup lights, cargo lights, and third brake lights.

Comparison between T10 and T15

Differences

T10                                             T15

Lasfit T10

Lasfit T15

T10

T15

T15 is commonly installed as a backup light, while T10 is commonly installed as an interior light. Therefore, T15 requires higher brightness than T10. To make the bulb brighter, the filament inside the halogen bulb glass tube needs to burn hotter, consuming more power. Therefore, T15 bulbs have a higher power than T10 bulbs.
- T15 halogen watt: 12-16W
- T10 halogen watt: 3-5W

Furthermore, LED bulbs themselves can emit different colors of light, while T10 and T15 halogen bulbs need to have their glass tubes coated with the desired colors to achieve different lighting effects. Lasfit provides various colors of T10 LED bulbs, including white, amber, red, golden yellow, green, pink, blue, and ice blue, and also offers red and white T15 LED bulbs. 

T10

T15

Similarities

Although T10 and T15 have different sizes, their bulb bases are the same. Because they have the same bulb base, it means that regardless of the size of the tubular glass, they can be plugged into the same connector.

Although T10 and T15 bulbs can be installed interchangeably, it is not recommended to do so for the following reasons:
- If T15 is installed in the position of T10, the longer T15 bulb may not fit due to limited space.
- If T10 is installed in the position of T15, the higher power required for T15 may damage the T10 bulb.

Installation method

The installation of T10 and T15 bulbs is very simple. You only need to remove the original bulbs that need to be replaced and install the LED bulbs without any modification. The steps for installing T10 as map lights are provided as an example.

1. Find the map light that needs to be replaced and use tools to pry and remove the cover.

2. Remove the factory T10 halogen bulb, and make sure to do this while the lights are turned off.

Compare the effect between the installed LED T10 and the halogen T10 bulb.

LED                                                  halogen

Effect demonstration of common installation positions for T10 and T15 bulbs

T10

T15

Conclusion

T15 and T10 bulbs have some differences in shape, size, and usage. Both types of bulbs have their characteristics and suitability for both interior and exterior lighting in vehicles. When purchasing and replacing bulbs, it is important to understand the specifications and purposes of the bulbs you need to choose the right ones for your needs.
Have you already upgraded your backup lights and interior lights to LED? Feel free to share your experience in the comments below! If you haven't installed them yet, now is the time! Visit https://www.lasfit.com/ and enter your vehicle's make, model, and year to find the suitable LED bulbs for your vehicle. We are looking forward to your feedback!