Why are my car mirrors blue?

Blue car mirrors are typically an intentional feature, not a defect. The blue tint usually comes from anti-glare or heat-reducing coatings, such as auto-dimming technology, or from blue-tinted glass on exterior mirrors. In most cases, the blue hue signals a design choice meant to improve visibility and comfort while driving.

What blue tint on car mirrors can indicate

The following explanations cover the common sources of a blue tint. Each category describes how the tint works and what to check on your vehicle.

Interior auto-dimming mirrors

Interior rearview mirrors may use an electrochromic coating that darkens in response to bright headlights from vehicles behind you. The tint often appears blue or blue-gray when active, even though the goal is glare reduction.

• Electrochromic glass darkens automatically to reduce glare from the headlights behind you.


• The resulting tint can look blue-tinged, especially in certain lighting conditions or angles.


• These mirrors may have a manual dimming switch or an “AUTO” setting to control the feature.

If the mirror no longer dims when bright lights hit it from behind, it could indicate a sensor or electrical issue and may require inspection.

Exterior mirrors with blue-tinted glass

Some vehicles use tinted glass for exterior mirrors to filter glare, UV, and heat. The tint is part of the glass itself and can give the mirrors a blue appearance under certain lighting and viewing angles.

• Tinted exterior mirror glass helps reduce glare and sun exposure on the mirror surface.


• The blue hue comes from the glass tint rather than an electronic dimming feature.


• Changing the tint typically requires replacing the mirror glass or choosing a different glass option from the factory or aftermarket.

Exterior blue tint is generally a normal design choice and not a defect. If you notice unusual distortion or damage, consult a professional.

Aftermarket tint films or replacements

If you recently had the mirrors replaced or applied aftermarket tint films, the blue tint could be a result of those modifications.

• Tint films or blue-tinted replacement mirrors can create a uniform blue hue across the surface.


• Tint levels can affect reflection clarity and visibility, especially at night or in bad weather.


• Local laws may regulate mirror tint levels on exterior surfaces, so verify compliance before or after installation.

Modifications can explain a newly noticeable blue tint; if you didn’t authorize changes, check with your vehicle’s service history or supplier.

How to identify which type you have on your car

Use this quick checklist to determine the source of the blue tint on your mirrors.

• Look for a sensor or auto-dimming controls on the interior rearview mirror and check for an “AUTO” label or a dimming switch.


• Examine exterior mirrors for a uniform blue tint across the glass, which suggests tinted glass rather than a dimming mechanism.


• Consult your owner’s manual or contact the dealership to confirm whether your model includes auto-dimming interior mirrors or tinted exterior glass as standard or optional equipment.


• Consider recent work on the mirrors—replacement, cleaning, or film application—to determine if tinting changes came from service or aftermarket work.

Knowing whether the tint is electronic (auto-dimming) or glass-based helps you decide on maintenance or potential replacements.

What to do if you want to adjust or remove the tint

Depending on the source of the blue tint, your options differ:

• Interior auto-dimming: Some models let you disable dimming via a switch or settings screen; check the manual for instructions.


• Exterior tinted glass: Replacing the exterior mirror glass with a non-tinted option is possible but may involve a professional swap and cost.


• Aftermarket tint films: If you choose to remove or change tint, ensure the work complies with local laws and does not reduce safety or visibility.

Always consider safety and legal guidelines when adjusting mirror tinting or coatings.

Summary

Blue-tinted mirrors are commonly a sign of glare-reduction technology or tinted glass rather than a defect. Interior auto-dimming mirrors darken to reduce headlight glare and may appear blue when active, while exterior mirrors can feature blue-tinted glass to filter heat and glare. By identifying whether your car’s blue tint comes from electronic dimming, tinted glass, or aftermarket modifications, you can decide if any maintenance or adjustment is needed and ensure you stay within local regulations.

What is the purpose of blue mirrors?

The polarization helps to block out horizontal light waves, which are the ones that cause glare. The blue mirror coating, on the other hand, helps to reduce the amount of light that enters the eyes by reflecting some of it back. This means that the eyes receive less light, making it easier to see in bright conditions.

Do rear view mirrors have night mode?

On manual tilt versions, a tab is used to adjust the mirror between "day" and "night" positions. In the day view position, the front surface is tilted and the reflective back side gives a strong reflection.

Why do mirrors get greener?

Mirrors have a faint green tint because they are not perfect reflectors of all light wavelengths. The glass used in mirrors has trace amounts of iron oxide, which slightly absorbs other colors while reflecting green light more efficiently. When light passes through the glass, reflects off the metallic backing, and then passes through the glass again, this slight green bias becomes noticeable.
 

• The glass itself isn't perfectly transparent: Standard glass contains iron oxide impurities, which give it a slight green cast. 
• Light travels through the glass twice: Light hits the reflective coating on the back of the mirror, travels through the glass to it, and then bounces back through the glass to your eyes. 
• This two-way trip accentuates the green: The combined effect of the light passing through the glass layer twice makes the slight green bias from the glass's impurities more pronounced. 
• The "infinity mirror" effect makes it obvious: This phenomenon is most easily seen when two mirrors are placed facing each other, creating an "infinity mirror" tunnel. The more reflections there are, the more the green tint builds up and becomes apparent in the repeated images. 

How do you remove oxidation from a mirror?

To clean an oxidized mirror, use a method that removes the oxidation without damaging the glass, such as buffing a small area with automotive polishing paste or jeweller's rouge and an all-cotton cloth. For general hazy spots, try using a solution of one part white vinegar to one part water, rubbing alcohol, or hydrogen peroxide on a microfiber cloth.
 
Method 1: For light haze (General cleaning)

• Vinegar and water solution: Mix one part white vinegar with one part distilled water in a spray bottle. Spray lightly onto the mirror or a microfiber cloth and wipe in an "S" pattern to clean and buff. 
• Rubbing alcohol: Dampen a cotton ball or microfiber cloth with rubbing alcohol and rub the hazy spots with circular motions. 
• Hydrogen peroxide: Spray a little 3% hydrogen peroxide onto a microfiber cloth, then wipe the mirror in an "S" pattern. 

Method 2: For persistent spots (Oxidation)

• Automotive polishing paste: Apply a tiny amount of automobile polishing paste to a clean, all-cotton cloth. Lightly rub a small spot near the edge of the mirror. 
• Jeweller's rouge: Rub a jeweller's rouge (also called red rouge) paste, powder, or stick onto the stains with a clean microfiber cloth. 
• Acetone: For very stubborn spots, apply acetone to an all-cotton cloth and wipe lightly. If it removes the film, you may need to recoat the mirror's backing to prevent further damage, according to this Cloudy Nights forum post. 

This video demonstrates how to remove the foggy haze from bathroom mirrors: 1:01GoCleanCoYouTube · Apr 16, 2025
Important considerations

• Protect the frame: Avoid getting vinegar on wooden or metal frames, as it can cause damage. 
• Use a microfiber cloth: Microfiber cloths are ideal because they are lint-free and do not leave streaks. 
• Use distilled water: For DIY solutions, distilled water is best to prevent the mixture from going bad too quickly.