Latest guides
Practical notes from the Guides section.
- H-Series Headlight Bulbs ExplainedCompare H1, H3, H4, H7, H8, H9, and H11 bulbs, including filament designs, bases, fitment checks, and safe replacement tips.
- How to Read a Headlight Bulb NumberLearn how to decode H7, H11, 9005, 9006, and other headlight bulb numbers, then verify the base, position, wattage, and bulb type.
- Are Headlight Bulb Sizes Universal?Headlight bulb sizes are not universal. Learn how to check base, connector, wattage, dimensions, and beam position before swapping bulbs.
- Automotive Light Bulb Size ChartUse this automotive light bulb size chart to compare common headlight, fog, brake, turn signal, reverse, interior, and license plate bulbs.
- Car Bulb Sizes Explained: Complete GuideLearn how automotive bulb sizes, codes, bases, voltage, wattage, halogen, HID, and LED fitment work—and how to verify the correct replacement.
What this site is for
Look up bulb positions, cross-references, and year-by-year fitment without guessing from a parts-counter printout.
Vehicle fitment
Make → model → year → positions and bulb codes from the Autotk catalog.
Bulb types
H11, 9005, 9012 and the rest — fitment counts, positions, and cross-reference notes from the catalog.
Guides
Practical swap notes: halogen vs LED, legality caveats, and common mistakes.