A standard air compressor can make a garage hard to work in, and hard to live next to. So "quiet" compressors have become their own category, sold on a single decibel figure. We read the product pages, spec sheets and manuals for sixteen compressors from eight brands, plus OSHA's guidance on noise.
The published figures run from 40 dB, for a model inside a soundproof cabinet, to 70 dB for the bigger garage units. Here is what they mean, which to buy, and the trade-off every quiet compressor makes.
Our 7 picks are listed above, with full specifications for each.
Almost no maker says how it measured
This is the thing to know before comparing. Of the sixteen compressors we checked:
- Only one states a distance. Campbell Hausfeld's spec table lists the DC080500 at 68 dBA at 3 ft.
- None names a test standard.
- The rest give a bare number. California Air Tools lists 56 to 70 dB, Makita 58 to 60 dB and DEWALT 60.3 dB(A), with no distance.
A reading taken close to a machine is higher than one taken farther away. So a compressor listed at 60 dB is not necessarily quieter than Campbell Hausfeld's 68 dBA at 3 ft. Use the figures to shortlist, not to split hairs.
Some brands publish no figure at all. We found none for Eagle, Ryobi, or Makita's and SENCO's other compressors. Harbor Freight's site blocked us, so we could not check its Fortress models.
Quiet costs air
Every quiet compressor makes the same trade. In our list, the lowest figures belong to the smallest machines:
- 56 to 59 dB: California Air Tools 1P1060S, Makita MAC100Q and Metabo HPT EC28M, delivering 0.7 to 1.20 CFM at 90 PSI.
- 60 dB class: California Air Tools 8010, Makita MAC210Q and Rolair JC10PLUS, at about 2 to 2.4 CFM. DEWALT's DXCMS20045US stands out at 5.0 CFM for 60.3 dB(A), but weighs 98 lbs.
- 70 dB: California Air Tools' 2.0 HP models, at 5.30 CFM.
Check the CFM at 90 PSI your tools need before you look at decibels. A brad nailer needs little. Sanders, grinders and spray guns need much more, and a compressor that cannot keep up will run constantly.
Why quiet compressors are quieter
The makers mostly credit a slower motor. California Air Tools says its motors run at 1680 RPM, and its cabinet model at 1400 RPM. Makita says its Quiet Series runs at 1,750 RPM, and Rolair describes low speed, oil-free drives. Rolair's loudest model we saw, at 79 dBA, runs at 3400 RPM.
Maintenance matters too. California Air Tools says to keep the intake filters attached so the unit runs as quietly as possible. Rolair says its thin reed valves play a major role in quiet running.
Setting it up
Give it space. Makita says to keep the compressor at least 12 inches from a wall. California Air Tools asks for 2 feet of clear space around and above the 8010.
Keep it on its feet. Makita says the compressor should rest securely on its rubber feet. Rolair says to keep the rubber vibration pads in place, and that running without them voids the warranty.
Use more hose, not an extension cord. Makita, DEWALT and Campbell Hausfeld all say to use a longer air hose instead of an extension cord. California Air Tools allows a cord no more than 25 feet long and at least 14 gauge.
Check before you run it indoors. DEWALT's product page promotes indoor use, but its manual says not to operate the unit indoors or in any confined area. Follow the manual for your model.
Drain the tank. Makita and DEWALT say daily or after each use. California Air Tools says every 1 to 2 days on average.
Protect your hearing anyway
A 60 dB compressor is quiet for a compressor, not silent, and air tools add their own noise. The manuals agree. Makita says to wear hearing protection against exhaust noise and noise during operation. DEWALT says to always wear ear protection. Campbell Hausfeld says to use hearing protection when operating the unit.
OSHA says exposure over 85 decibels can damage your hearing. Its rule of thumb: if you need to raise your voice to speak to someone 3 feet away, the noise may be over 85 dBA.
Mistakes buyers make
Buying the lowest number without checking the air. The quietest units deliver about 1 CFM.
Comparing a bare figure with one measured at 3 ft. They may not be measured the same way.
Running a small compressor flat out. California Air Tools suggests 1 HP units avoid running more than 30 to 45 minutes at a time.
Using a long, thin extension cord. California Air Tools warns it can overheat the motor.
Skipping hearing protection because the box says quiet. The makers still tell you to wear it.
How we chose
We read the manufacturer's US product page, specifications and, where we could open it, the manual for each compressor. We recorded each noise figure in the maker's own words, with any distance or standard it gave. We compared tank size, air delivery at 90 PSI, maximum pressure, pump type, weight and warranty, and recorded the price on the maker's own site where one was shown. We read OSHA's guidance on noise.
We did not measure decibels ourselves. We ranked first on published figures, then weighed air delivery, because a quiet compressor that cannot run your tools is no use. Makita, DEWALT, Metabo HPT, Rolair, Campbell Hausfeld and Milwaukee show no price on their own sites, so check the price on the day you buy.
New to the units? Read dBA explained. To decide what figure to aim for, see how quiet is quiet enough, room by room.
