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What else fits H11?

H11 does not correspond to a valid HTML heading element; the standard heading levels in HTML go from h1 to h6. Outside of markup, H11 appears as a code or designation in several domains, notably in medical coding (ICD-10-CM) and as a common automotive headlight bulb designation. This article examines where H11 shows up and what it can mean in those contexts.

H11 in HTML and web markup

In web markup, headings are defined by the elements h1 through h6. There is no h11 element. When building long documents or applications, you should structure content using the existing six levels and, if needed, reorganize sections rather than invent deeper heading tags.

Deeper headings and accessibility

To represent deeper structure without an h11 tag, consider reorganizing content into additional sections with their own h2–h6 headings, or use a logical table of contents. For accessibility, avoid creating nonsemantic heading levels or using ARIA to simulate levels beyond 6; instead, keep the document outline understandable by assistive technologies.

The result is a markup that preserves accessibility and semantic clarity while avoiding invalid or nonstandard elements.

Here are practical options for representing deeper sections when you run out of heading levels.

Use h1–h6 only and nest sections to reflect hierarchy instead of creating extra heading elements.

Structure content with multiple sections and subheadings (e.g., h2 followed by h3–h6), rather than introducing an h7 or beyond.

Rely on CSS for visual depth (font size, weight, margins) rather than implying deeper semantic levels.

When accessibility is a priority, ensure your document outline remains logical and navigable for screen readers rather than relying on nonsemantic hacks.

These practices help maintain a accessible, standards-compliant web document while still conveying a clear hierarchy.

Other contexts where H11 appears

Beyond markup, H11 is used in different systems to denote specific things. Understanding the context is essential to avoid misinterpretation.

Medical coding (ICD-10-CM): H11 serves as a heading for disorders of the lacrimal apparatus, with subcodes identifying particular conditions within that category.

Automotive lighting: H11 is a common designation for a 12-volt halogen headlight bulb, frequently used for low-beam or fog-light applications, with many aftermarket and OEM options available (including LED replacements).

Product catalogs and SKUs: In vendor inventory systems, H11 may be part of a model or SKU code, defined by the vendor’s own labeling scheme.

In each case, the exact meaning of H11 depends on the governing standard or the specific vendor documentation. When you encounter H11, identify the domain and consult the relevant manuals or specifications to confirm its meaning in that context.

Best practices for handling H11 in documentation and development

Clear labeling and documentation help prevent confusion when a label like H11 appears in multiple domains. The following guidelines aim to reduce ambiguity.

Determine the domain before interpreting H11 — HTML, healthcare coding, or product data each uses different semantics.

Preserve HTML semantics by using h1–h6 for headings and avoiding nonstandard tags such as h11.

When H11 appears in data fields, include a legend or metadata that explains its meaning in that dataset.

For accessibility, avoid substituting nonsemantic elements to represent headings; keep the document outline coherent for assistive technologies.

By applying these practices, teams can minimize misinterpretation and maintain consistent communication across disciplines.

Summary

H11 is not a valid HTML heading level; the standard heading elements go from h1 to h6. Outside HTML, H11 is used in various domains—most notably ICD-10-CM coding for lacrimal apparatus disorders and as a common automotive headlight bulb designation. The meaning of H11 is domain-specific, so always verify the context and consult the relevant standards or vendor documentation to determine what H11 represents in any given situation.

Are H7 and H11 bulbs the same?

No, H7 and H11 bulbs are not the same and cannot be used interchangeably because they have different base designs, socket types, and dimensions. The primary differences are their base configuration and the type of application they are designed for; H7 bulbs are often used for both low and high beams, while H11 bulbs are typically for low beams or fog lights.
Key differences between H7 and H11 bulbs

Feature	H7	H11
Base/Socket Design	PX26d base with two bare prongs	PGJ19-2 base with two encased prongs
Application	Low and high beams	Low beams and fog lights
Dimensions	Larger diameter (~26 mm)	Smaller diameter (~19 mm)
Interchangeability	Not interchangeable with H11	Not interchangeable with H7

Check your owner's manual: This is the most reliable source for the correct bulb type for your vehicle.
Examine the existing bulb: Take out the old bulb and look for the bulb number printed on its base.
Use an online bulb finder: Many automotive parts websites have tools that can look up the correct bulb for your specific vehicle.

Can I replace H11 with 9005?

No, you cannot use a 9005 bulb instead of an H11 because they have different bases, wattages, and physical dimensions, making them physically incompatible and unsafe to force into each other's sockets. H11 bulbs are typically used for low beams, while 9005 bulbs are often used for high beams, and trying to interchange them can damage the socket or cause improper light output.
Key differences between H11 and 9005 bulbs

Feature	H11	9005 (HB3)
Base Type	PGJ19-2	P20d
Typical Use	Low beams or fog lights	High beams
Wattage	55W	65W
Total Height	58 mm	78 mm
Bulb Diameter	12 mm	16 mm
Plug Width	24 mm	46 mm
Locking Tabs	Metal locking tabs	Plastic locking tabs

Different bases: The bases are designed differently (PGJ19-2 vs. P20d) and will not connect securely to the opposite socket.
Physical size: The 9005 bulb is larger in several dimensions, including height and diameter, and will not physically fit into an H11 housing.
Wiring and wattage: They have different wattage ratings (55W55 cap W55𝑊 for H11 vs. 65W65 cap W65𝑊 for 9005), and the electrical connectors are different, so they are not wired to function correctly in the other's socket.

What to do instead

Check your vehicle's manual: Always verify the correct bulb size for your specific make and model using your car's owner's manual to ensure you purchase the right bulb.
Do not force it: Never attempt to force a bulb into the wrong socket, as this can cause damage to the socket, the bulb, and the electrical system.
Consider conversion kits carefully: While some companies offer conversion kits to adapt H11 sockets for 9005 bulbs (or vice versa), these can lead to improper beam patterns and are not recommended unless you understand the risks and your vehicle's housing can handle it, {says link: Hawkglow https://hawkglow.com/blogs/news/h11-and-9005-led-bulbs-are-they-interchangeable}.

What do H11 LED headlights fit?

H11 LED bulbs are compatible with many modern vehicles from various manufacturers, including common models like the Toyota Camry, Honda Accord, Ford F-150, and Chevrolet Malibu. They are used for both low beam and fog lights, and sometimes for high beams, so it's crucial to check your specific car's manual to confirm compatibility and the correct bulb type.

Common vehicle makes and models that use H11 bulbs

Toyota: Camry, Corolla, RAV4, Tacoma, Highlander
Honda: Accord, Civic, CR-V, Pilot, Ridgeline
Ford: F-150, Explorer, Escape, Edge
Chevrolet: Malibu, Silverado, Equinox
Nissan: Altima, Rogue, Sentra
Hyundai: Sonata, Tucson
Subaru: Outback, Forester
Mazda: CX-5, Mazda 3
Kia: Optima, Sportage
BMW: 3 Series, 5 Series, X5

Important considerations

Always check your manual: Vehicle designs vary even within the same model year. Always consult your owner's manual to confirm that H11 is the correct bulb size for your car's headlights or fog lights.
Check the application: H11 bulbs are commonly used for low beams and fog lights, but some vehicles may use them for high beams or have different bulb types for each function.
Be aware of bulb variations: There are different versions of bulbs that look similar but are not cross-compatible (e.g., H11 vs. H16 Type B).
Professional advice: If you are unsure, consult a professional or refer to the vehicle's manual before purchasing and installing any bulbs, especially with electronic systems.

What is H11 compatible with?

H11 bulbs are compatible with a wide variety of vehicles, particularly for low-beam headlights and fog lights, across many major brands like Toyota, Honda, Ford, and Chevrolet.

Kevin Bennett

Company Owner

Kevin Bennet is the founder and owner of Kevin's Autos, a leading automotive service provider in Australia. With a deep commitment to customer satisfaction and years of industry expertise, Kevin uses his blog to answer the most common questions posed by his customers. From maintenance tips to troubleshooting advice, Kevin's articles are designed to empower drivers with the knowledge they need to keep their vehicles running smoothly and safely.