The Best Spark Plugs

A vital component of any engine, choosing a replacement spark plug for your engine isn’t as simple as it once was, with plenty of types and choices now available. Finding the best spark plugs for your needs means reading reviews, studying product features, and diving into the ins and outs of available metal types. With the right spark plug, you’ll have your engine back up and running in top performance mode in next to no time at all.

We reviewed dozens of spark plugs to identify the best of the best, based on Amazon reviews, how well they performed in performance tests, cost, and other considerations. We narrowed our search down to 5 of the top-rated spark plugs motorheads can purchase to ensure a smooth-running ride.

Top Pick
NGK 6619 Iridium Spark Plugs

A premium spark plug in a convenient multi-pack

$28.00 USD

We’ve identified NGK 6619 Iridium Spark Plugs as the best spark plug out there. With a premium coating in a convenient multi-pack, this spark plug is one that will keep your vehicle running in tip top shape. These benefits allow you to enjoy a reliable, smooth, and comfortable ride for many miles to come.

The 5 Top-Rated Spark Plugs for 2018

Editor's PicksBrandRating
Best OverallNGK 6619 Iridium Spark Plugs4.4
Runner UpBosch 4417 Platinum+4 FGR7DQP Spark Plug4.6
Best Budget BuyDenso (4504) PK20TT Platinum TT Spark Plug4.5
Best Iridium Spark PlugsNGK 5464 BKR5EIX-11 Iridium IX Spark Plug4.5
Best Platinum Spark PlugsNGK (7092) BKR6EGP G-Power Spark Plug4.3

*Ratings are from Amazon at the time of publication and can change

Our Top Pick: NGK 6619 Iridium Spark Plugs

The NGK 6619 Iridium Spark Plugs are our pick for the best spark plugs as they are one of the most premium spark plug offerings available. The multi-pack is convenient for when multiple plugs need replaced, and even if they don’t, you can store the extras away for later when the others eventually need replaced as well. The iridium material used for these plugs provides up to 25% longer use compared to platinum spark plugs.

Those who purchased and reviewed this spark plug appreciated that although the cost of this spark plug was high due to the fact it comes in a multi-pack, the overall cost per plug was still reasonable for the quality it provides. Many users were impressed that these plugs performed better than the OEM ones, and that they fit perfectly in a number of different engines.

With a cost of about $7 each, it’s a surprisingly affordable option, and the quality craftsmanship associated with the brand, as well as the ease of installation and use more than justifies that price. It has a rating of 4.4 on Amazon with nearly 200 people reviewing it, which we think goes a long way in convincing auto enthusiasts to make the investment.

NGK 6619 Iridium Spark Plugs Key Features:

  • Lasts longer than copper and platinum spark plugs
  • Super fine electrode wire for increased efficiency
  • Comes pre-gapped at .043

Runner-Up: Bosch 4417 Platinum+4 FGR7DQP Spark Plug

Runner Up
Bosch 4417 Platinum+4 FGR7DQP Spark Plug

German engineering with an innovative design and excellent performance

$5.93 USD

The Bosch 4417 Platinum+4 FGR7DQP Spark Plug is our runner up choice for the best spark plug, thanks to its unique plug tip design which has been completely re-worked from the ground up. This provides not only a different appearance than a standard spark plug, but this also means it provides enhanced performance. The plug-and-play installation makes it a breeze for swapping out your old spark plugs when it’s time for a change.

Those who purchased and reviewed this spark plug appreciated that these plugs ran longer than less expensive ones, and were impressed with the torque, power, and overall performance they provided. A premium manufacturer of electrical goods, Bosch is a name that many consumers associate with quality products and customer service.

At a cost of around $18, it certainly doesn’t come cheap, but the quality craftsmanship associated with the brand, as well as the ease of setup and use more than justifies that price. It has a rating of 4.6 on Amazon with more than 200 people reviewing it, which we think goes a long way in convincing gear heads that this is another spark plug that’s worth the investment.

Bosch 4417 Platinum+4 FGR7DQP Spark Plug Key Features:

  • Utilizes 4 yttrium-enhanced electrodes
  • Low maintenance design
  • Increased longevity

Budget Pick: Denso (4504) PK20TT Platinum TT Spark Plug

Best for Budget
Denso (4504) PK20TT Platinum TT Spark Plug

A budget-friendly option offering reliable performance

$5.35 USD

The Denso (4504) PK20TT Platinum TT Spark Plug is our choice for the best budget-friendly spark plug as it provides nearly all the performance-enhancing features of iridium but at a fraction of the cost. While a platinum spark plug such as this can provide less longevity than their iridium counterparts, the Denso 4504 isn’t far behind. It uses a platinum disc and electrode tip to provide solid performance.

Those who purchased and reviewed this spark plug appreciated that it was compatible with a number of different vehicle makes and models, and came highly recommended by their mechanic. A couple of reviewers noted that they needed to re-gap their plug to fit, but most had no issues.

With a price tag of about $3, this spark plug is a solid choice for those looking for a spark plug option on a budget. It has a rating of 4.5 on Amazon with nearly 400 people reviewing it, which we think goes a long way in convincing motor heads that this budget-friendly pick is just as good at improving engine performing as its more expensive counterparts.

Denso (4504) PK20TT Platinum TT Spark Plug Key Features:

  • Uses purified alumina powder as an insulator
  • Electrode has an 11 mm width
  • Platinum twin tips

Best Iridium Spark Plugs: NGK 5464 BKR5EIX-11 Iridium IX Spark Plug

Best Iridium Spark Plug
NGK 5464 BKR5EIX-11 Iridium IX Spark Plug

Specially designed with high performance vehicles in mind

$20.00 USD

The NGK 5464 BKR5EIX-11 Iridium IX Spark Plug is our choice for the best iridium spark plug, and has been specially designed with high performance vehicles in mind. The thin, 0.6 mm electrode helps to increase engine power and performance, while the corrugated ribs on the insulator work to help prevent flashover. It offers improved ignitability and throttle response.

Those who purchased and reviewed this spark plug appreciated that these plugs come pre-gapped in the size specified, and were very easy to switch out. One reviewer even mentioned switching back to this plug from another brand after being disappointed in their vehicle’s performance. Many comments mentioned the quality of the plugs, having been made in Japan.

At a cost of around $6, it’s not particularly expensive or inexpensive, but the quality craftsmanship associated with the brand, as well as the ease of setup and use more than justifies that price. It has a rating of 4.5 on Amazon with nearly 250 people reviewing it, which we think goes a long way in convincing auto enthusiasts to make the investment.

NGK 5464 BKR5EIX-11 Iridium IX Spark Plug Key Features:

  • Triple gasket seal eliminates combustion gas leakage
  • Trivalent metal plating
  • A longer insulator nose helps to prevent fouling

Best Platinum Spark Plugs: NGK (7092) BKR6EGP G-Power Spark Plug

Best Platinum Spark Plug
NGK (7092) BKR6EGP G-Power Spark Plug

A high performance plug without the high price tag

$5.42 USD

The NGK (7092) BKR6EGP G-Power Spark Plug is our pick for the best platinum spark plug as it comes complete with a nice and thin 0.6 mm tip, which is ideal for providing increased engine power and performance, while the brand’s distinctive longer insulator nose helps to prevent fouling for increased longevity. They are available in a single or multi-pack, which is convenient when you have multiple plugs that need replaced.

Those who purchased and reviewed this spark plug appreciated the value it provided, along with the OEM-level quality. Reviewers were happy that these plugs fit various makes and models of cars, and even some older vehicles. Users liked that these plugs came pre-gapped, but there were a couple of reviews that mentioned the dimensions being off, so it’s worth double checking before you install them.

At a cost of around $4, it’s a surprisingly affordable choice, and the quality craftsmanship associated with the brand, as well as the ease of setup and use more than justifies that price. It has a rating of 4.1 on Amazon with more than 250 people reviewing it, which we think goes a long way in convincing motor enthusiasts that these spark plugs are worth the investment.

NGK (7092) BKR6EGP G-Power Spark Plug Key Features:

  • Tin tip
  • Provide high durability
  • Trivalent metal plating

Who Should Buy a Spark Plug?

A spark plug is must for those who run any sort of gas-powered motor. This could be in a vehicle such as a car or truck, tools such as lawn mowers and chainsaws, or even a generator.

A spark plug is only required for motors which run on gasoline as fuel; it is not required for diesel-powered machines.

If your engine is misfiring, having trouble starting, or other performance issues, it is worth investigating if you need to replace your spark plug.

Top Pick
NGK 6619 Iridium Spark Plugs

A premium spark plug in a convenient multi-pack

$28.00 USD

Important Features to Consider

Not all spark plugs are created equal. A spark plug should fit the make and model of your engine, and bring the best performance out of the motor. Here’s what to consider when evaluating the options in search of the best spark plug for your needs:

  • Material. Most standard spark plugs are made from copper, however, there are others that are made with platinum or iridium. The type of spark plug you need will be listed in your owner’s manual for the engine which needs the spark plug replaced. If you cannot find your owner’s manual, ask an auto parts store for the manufacturer’s recommended plug. Do not downgrade to a less expensive plug if your vehicle came with a premium spark plug, as any initial savings will quickly be offset by a shorter service life and reduced gas mileage. Iridium is the best material for spark plugs, but it’s also the most expensive.
  • Long-lasting. Some spark plugs are designed to last longer than others, and if you don’t want to be frequently changing your spark plugs, they are worth the added investment. Platinum, yttrium and iridium spark plugs are more expensive than copper spark plugs, but these premium coatings provide much better wear resistance.
  • Adjustable vs. fixed gap. The spark plug gap is the amount of space between the center and side electrodes of each spark plug, and is very important when it comes to choosing the right spark plug for your needs. Make sure you select a fixed gap spark plug in the right size, or adjust the gap on each plug before installation.
  • Price point. Finally, consider how much you are willing to spend on a spark plug. Spark plugs vary in price from $1-$15 or more.

Frequently Asked Questions

What are spark plugs and how do they work?

A spark plug is a component of a ignition system within a motor. A spark plug works by igniting an air/fuel mixture. It does this by transmitting electrical energy through itself, jumping the gap between the plugs’ firing end, as long the voltage supplied to the plug is high enough. The electrical spark that is created then ignites the air/fuel mixture within the combustion chamber in order to move the pistons, which drive the crank and give the engine power.

Do spark plugs make a difference in performance?

Yes, spark plugs make a difference in performance. A foul or worn spark plug will give less power and performance, compared with a new plug which is properly gapped. If you are noticing performance issues with your vehicle or tool, it is worth checking the spark plug for problems.

What are the symptoms of bad spark plugs?

The symptoms of bad spark plugs include misfiring, which is when the engine makes a rough sound — this could be clunking or banging types of noise. An engine might be hard to start if the spark plugs are bad, and you might even notice that you get poor fuel mileage, as the spark isn’t strong enough to burn the air/fuel mixture in the combustion chamber, and as such calls for more fuel. A lack of acceleration and/or torque is another sign of a bad or worn spark plug.

The color of your spark plug will tell you the health of your engine’s fuel burn, and provide guidance on how to remedy any issues. For example, white means that there is something causing the plug to run too hot, while black can indicate there is a weak spark or an overly rich fuel mixture. A wet spark plug is indicative of engine flooding or a bad ignition cable.

How often do you need to change your spark plugs?

How often you need to change your spark plugs depends on a number of factors, including mileage, running hours, oil leaks, high revs, and the type of spark plug you’re using. Most automotive manufacturers will include recommendations for how frequently you should change your spark plugs — usually about every 30,000 miles or so. That said, if you notice any of the symptoms of bad spark plugs mentioned above, the odds are good that it’s time to have your plugs replaced.

Other Spark Plugs We Reviewed

Top Pick
NGK 6619 Iridium Spark Plugs

A premium spark plug in a convenient multi-pack

$28.00 USD

We looked at 20 other spark plugs. Even though they didn’t make our 5 best spark plugs list, they’re the best of the rest and each is still a great option for your motor repair needs. The information you’ll need to compare each one is included with the listing.

Iridium Spark Plugs

ACDelco 41-103 Professional Iridium Spark Plug

ACDelco 41-103 Professional Iridium Spark Plug

This spark plug boasts an iridium fine-wire electrode which provides excellent engine idle stability and smooth performance.

Key Features:

  • Reliable cold starting
  • Allows for quick acceleration
  • Unique design helps prevent combustion leakage

Cost: $7

NGK BKR7EIX Iridium IX Spark Plug

NGK BKR7EIX Iridium IX Spark Plug

This iridium spark plug provides motor enthusiasts with extreme ignitability, improved throttle response, and superior anti-fouling for improved performance.

Key features:

  • Available in single or multipacks
  • Includes a 0.6mm laser welded fine iridium tip
  • Triple gasket seal eliminates combustion gas leakage

Cost: $8

NGK (6994) Laser Iridium Spark Plug

NGK (6994) Laser Iridium Spark Plug

This spark plug has been designed for long lasting reliable use, and features a laser welded iridium center electrode tip and solid copper core.

Key features:

  • Available in single or multipacks
  • Suitable for different vehicle makes and models
  • Solid copper core and nickel tipped electrode

Cost: $9

NGK 6418 BKR6EIX Iridium IX Spark Plug

NGK 6418 BKR6EIX Iridium IX Spark Plug

This spark plug has been designed with the performance enthusiast in mind, and features improved  ignitability, throttle response, and superior anti-fouling features.

Key features:

  • Suitable for high-performance engines
  • Superior anti-corrosion and anti-seizing properties
  • Triple gasket seal eliminates combustion gas leakage

Cost: $7

Champion RER8ZWYCB4 (9407) Iridium Spark Plug

Champion RER8ZWYCB4 (9407) Iridium Spark Plug

This spark plug comes complete with a fine-wire iridium center electrode and a platinum ground to help deliver maximum life from the plug.

Key features:

  • Compatible with any engine type
  • Uses a exclusive heat-active alloy
  • Pre-gapped for ease of use

Cost: $7

Motorcraft SP534 Spark Plug

Motorcraft SP534 Spark Plug

While this spark plug carries the Motorcraft name, it’s actually made by NGK, so you’re getting a quality plug at an affordable price.

Key features:

  • Suitable for different vehicle makes and models
  • Pre-gapped for ease of use
  • Ideal for vehicles with ecoboost

Cost: $7

ACDelco 41-110 Professional Iridium Spark Plug

ACDelco 41-110 Professional Iridium Spark Plug

This iridium spark plug comes in a convenient 8-pack to provide an economical solution for replacing your spark plugs.

Key Features:

  • Pre-gapped to .040
  • One piece suppressor seal helps block radio frequencies which affect vehicle electronics
  • Iridium fine-wire electrode

Cost: $5

Platinum Spark Plugs

NGK 7090 BKR5EGP G-Power Spark Plug

NGK 7090 BKR5EGP G-Power Spark Plug

Available in a single or multi-pack, this spark plug helps improve vehicle fuel efficiency, lower emissions, and provide quicker starts.

Key Features:

  • Offers a 0.6mm laser welded fine platinum tip
  • Corrugated ribs on the insulator help to prevent flashover
  • Trivalent metal plating

Cost: $5

NGK (3199) BKR6EQUP Laser Platinum Spark Plug

NGK (3199) BKR6EQUP Laser Platinum Spark Plug

Designed with quality and reliability in mind, this spark plug has been constructed from durable materials to provide thousands of worry-free miles.

Key features:

  • Corrosion- and abrasion-resistant design
  • Ceramic insulator with copper core
  • Triple interior seal

Cost: $7

Motorcraft SP-515 Spark Plug

Motorcraft SP-515 Spark Plug

While this spark plug carries the Motorcraft name, it’s actually made by NGK, so you’re getting a quality plug at an affordable price.

Key Features:

  • Designed, engineered, and recommended by Ford Motor Company
  • Pre-gapped for ease of use
  • Platinum offers a high melting point

Cost: $5

NGK (3403) TR55GP G-Power Spark Plug

NGK (3403) TR55GP G-Power Spark Plug

This platinum alloy spark plug provides outstanding performance and improved fuel efficiency over copper models, and helps to lower vehicle emissions, while providing quicker starts.

Key features:

  • Includes a 0.6mm laser welded fine Platinum tip
  • Trivalent metal plating
  • Triple gasket seal eliminates combustion gas leakage

Cost: $4

Copper Spark Plugs

Champion RC12YC (71G) Copper Plus Small Engine Replacement Spark Plug

Champion RC12YC (71G) Copper Plus Small Engine Replacement Spark Plug

This copper spark plug helps to resist fouling while providing a reliable ignition source for your motor needs.

Key Features:

  • Corrosion-resistant
  • Ideal for marine applications
  • Built to ISO and SAE performance standards

Cost: $5

Arnold First Fire FF-10 Replacement Spark Plug

Arnold First Fire FF-10 Replacement Spark Plug

This replacement spark plug offers dependable performance and consistent starts for motor enthusiasts.

Key Features:

  • Available in different models
  • Fouling resistant
  • Compatible with many major brands

Cost: $3

Champion RCJ6Y (852) Copper Plus Small Engine Replacement Spark Plug

Champion RCJ6Y (852) Copper Plus Small Engine Replacement Spark Plug

This copper spark plug offer superior corrosion resistance in order to resist fouling and provide reliable performance.

Key Features:

  • Dependable performance
  • Suited for lawn and garden and snow applications
  • Includes step-by-step instructions

Cost: $6

Champion RDZ4H (979) Copper Plus Small Engine Replacement Spark Plug

Champion RDZ4H (979) Copper Plus Small Engine Replacement Spark Plug

This copper spark plug has been designed with small engines in mind, and is thus compatible with both lawn and garden and snow applications.

Key Features:

  • Helps resist fouling
  • Provides superior corrosion resistance
  • Increased conductivity for good overall wear

Cost: $6

NGK (4929) DPR8EA-9 Standard Spark Plug

NGK (4929) DPR8EA-9 Standard Spark Plug

Available in single or multi-packs, this spark plug boasts a solid copper core for greater spark, while the longer insulator nose helps to prevent fouling.

Key Features:

  • Corrugated ribs on the insulator help to prevent flashover
  • Zinc dipped shell for anti-corrosion properties
  • Triple gasket seal eliminates combustion gas leakage

Cost: $5

Champion RJ19HX (973) Copper Plus Spark Plug

Champion RJ19HX (973) Copper Plus Spark Plug

This copper spark plug offer superior corrosion resistance in order to resist fouling and provide reliable performance.

Key Features:

  • Suited for lawn and garden and snow applications
  • Includes step-by-step instructions
  • Over 100 years of innovation

Cost: $7

E3 Spark Plug E3.36 Powersports Spark Plug

E3 Spark Plug E3.36 Powersports Spark Plug

Suitable for a variety of makes and models of vehicles, this spark plug has been specially designed to help eliminate carbon deposits to provide dramatically longer plug life.

Key Features:

  • Includes a 5 year warranty
  • Provides up to 100,000 miles of performance
  • Improves power and fuel efficiency

Cost: $8

NGK 7131 BPR6ES Standard Spark Plug

NGK 7131 BPR6ES Standard Spark Plug

Providing more bang for your buck thanks to its muli-pack design, this copper spark plug offers superior heat dissipation and conductivity, while the longer insulator nose helps to prevent fouling.

Key Features:

  • Corrugated ribs on the insulator help to prevent flashover
  • Zinc dipped shell for anti-corrosion properties
  • Triple gasket seal eliminates combustion gas leakage

Cost: $3

Champion RE14MCC4 (570) Copper Plus Spark Plug

Champion RE14MCC4 (570) Copper Plus Spark Plug

This copper spark plug provides an affordable fix for engine woes, and features a patented Ultraseal coated shell for maximum corrosion resistance.

Key Features:

  • Suitable for different vehicle makes and models
  • Pre-gapped for ease of use
  • Built to ISO and SAE performance standards

Cost: $2

Products You May Be Interested In: