The primary use for a portable compressor (certainly when it comes to motoring) is to top off your tires … just squeezing a few psi back into them when they’re slightly low. A small battery powered inflator isn’t designed to compete with a shop compressor, and it won’t run pneumatic tools, inflate bouncy castles, heck it may even struggle to inflate a dinghy, but that’s missing the point.
The Best Portable Tire Inflator
The best portable tire inflators are all a handy size, which means you can keep them in the trunk without taking up too much space. You should understand though, that some of the portable inflators have a fairly short duty cycle. They can only run for a limited time before needing to be stopped to cool down, and while we’re talking about limitations, you need to figure out what you want from it – inflating a huge truck tire is a no-no for example, at least for the smaller tire inflators, as is anything that’s high pressure …
I’ve chosen six tire inflators, all very good in their own way, but depending on your exact use, you may find one or two better suited to you need, so as usual, you need to have a think about what you’ll be doing before purchasing.
This is kind of mid-range pricing, and although it offers some pretty useful features, the big ‘must know’ fact here is that it has a maximum pressure of just 70psi – ideal for regular cars, bikes, bicycles, and light trucks, but start going up in size and pressure, and you’ll need to look for something different.
The EPAuto portable inflator is fitted with a 12v accessory plug, it’s rated at between 10-15A, or 120-180W, so there shouldn’t be any issues with running it through your accessory outlet, and the hose (which is around 2.5’ in length) has a screw-on Schrader valve adaptor, although it does also come with a long & short cone and needle valve adaptor.
It also has a digital display which can display four different units of measurement – BAR, PSI, KPA and KG/CM, and you can preset the unit for an auto shut off at a predetermined pressure, in actual fact, the unit pumps slightly over the set pressure for the inevitable air loss while decoupling. The compressor shifts around 1.06CFM (Cubic Feet Minute) which is about average.
Other good features are the included LED flashlight built-in, an overheat protection to save itself from damage under hard use, and the cord storage is perhaps the best out of all six inflators, they’ve done a really neat job to make it fit properly, all 9’ (approximately) of it.
All in, the EPAuto compressor is a great all-rounder that will work for near all situations and priced for great value for money.
Clarifications first: the direct-drive refers to the need to be attached directly to the battery with the alligator clips, and the ‘2X’ is actually something unique in this category – it refers to a dual cylinder inflator for maximum speed – Slime says it will inflate a standard car tire in less than two minutes.
This is a neat kit – everything stores away in the hard carry case, including the almost professional styled coiled inflation hose, which between that and the power cord, gives you a total reach of 30’ – that’s enough for regular domestic use, you won’t need anything longer.
There’s an analog gauge in-line on the inflation hose, again it’s semi-accurate (same as the all the others here) but I’d always check pressures with a separate gauge when it’s important. Finally, there’s a bright LED work light that’s been built-in, and I can honestly say that I’ve never needed one.
It’s at the higher end of the pricing structure, but as an all-rounder, and the fact that it all comes as a complete kit with a good case is a bonus.
There are a couple of noticeable differences here – the first being that this portable air compressor doesn’t use a 12v accessory outlet – it has alligator clips for direct connection to the battery, and the second being that the body of this compressor is metal, and looks really robust – I like it.
The Viair 88P pumps around 1.47cfm of air, making it one of the fastest inflators in the group. Rated a maximum of 120 PSI, Viair says that it can be used with huge tires up to 33” in size (a regular sedan is around 18”). The maximum amperage draw is 20A, which is why it needs a direct connection to the battery rather than power through the accessory outlet, and ideally, the vehicle that it’s attached to should be running.
The power cord is an average 10’ in length, but the inflator hose is a huge 16’ – you’ll have no issues reaching around any vehicle with this. The other neat touch is the adaptor on the inflation hose (Schrader valve) is made from brass, it will stand a lifetime of use without having a problem.
There’s a built-in pressure gauge, but no auto shut off feature, and for me, the biggest feature that’s missing is that there’s no carry or storage bag – it’s going to get messy.
The JACO tire pump seems to be a step-up from the EPAuto in some senses. It can pump up to 100psi (against the 70psi for the EPAuto) but shifts around 25 liters per minute of air, which works out to just under 0.9cfm, meaning that it will take slightly longer to inflate a tire.
However, it’s pretty similar – it uses smart pressure technology to auto shut off and preset, has a digital pressure gauge & display which can be swapped between BAR, PSI and KPA and it all plugs into the cars accessory outlet; it’s rated at 10A.
I like the fact that the hose and power cord are slightly longer – a 10’ power cord for example, and that the hose itself is a heavy-duty woven cloth material covering, it takes me right back to the days of the old foot pumps that came with similar. Another great feature is the built-in flashlight which has four different modes – off, regular flashlight, flashing red light and emergency SOS strobe.
The compressor can be used for around 30 minutes before needing to cool off for 15 minutes, which is quite a high rate of work for one of these small inflators. The manufacturers say that it’s accurate to within +/- 1psi – even if that’s slightly out, it’s close enough to not have to worry about it, get yourself a separate gauge to verify it.
Another fast inflator – moving 38 liters of air per minute, which is around 1.35cfm. The reach is a little short when compared to the Slime or Viair compressors, at just 13’, but it should be enough for regular domestic use on sedans or hatches, perhaps a little lacking for the larger SUVs or trucks.
It uses a digital gauge which allows for an auto shut off feature, and P.I. Auto Store state that it can inflate a regular tire from flat to 30psi in around 3 minutes – which shows you how fast the Slime compressor is, but to be fair, the PI compressor is powered through the 12v accessory outlet, not as a direct power source from the battery.
Best of all, this device comes complete with a quality carry case, which stores the compressor, hose, power cord, adaptors, and 4x spare dust caps, and PI Auto Stores also make an adaptor to allow it to be used from a regular wall outlet. I also appreciate a bright (100 lumens) LED work light, which can swap to a red SOS signaling lamp – ideal for visibility if you were stuck in the wilds.
I’ve included the Ryobi air compressor, although this is more of a handheld inflator, just because it really is super handy to have around, being honest if inflating tires with it is your primary use, this isn’t the compressor for you. Aside from anything else, the power button is just that – a button and not a switch, so you need to keep pressure applied to it for the duration.
The price of the Ryobi inflator is low, but you should remember that the pricing structure really only works for you if you have other Ryobi tools that use the ONE+ battery system. There is no battery or charger included with this cordless air inflator, so you either need one to start with, or you need to factor in buying a battery & charger separately.
That’s it for the irritations, the rest is all positive. The Ryobi P737 will pump up to 150psi, which is the highest pressure here, and of course, is completely cordless, there’s no worrying whether it will reach around the vehicle, or even need a vehicle if you’re out enjoying nature or something. It’s small enough to be thrown into a backpack.
Equipped with a 20” hose, the unit allows slightly more convenient during air pumping, and the hose has a quick release coupler for a Schrader valve rather than a screw-on coupler. It does come with a couple of other adaptors … ‘leisure adaptors’ … which is basically a cone and the regular needle adaptor for inflating balls and the like.
Overall, it’s a really useful inflator for most things, great if you’re an outdoorsy kind of person.
All six of these car tire inflators have a built-in pressure gauge, and while it’s a handy feature to have, you’ll typically find that most of them are more of an indication to the pressure, rather than 100% accurate, even the ones listed as accurate to +/- 1psi may not actually be that close. They’re good enough for general use, but if you need an absolute accurate reading, I’d recommend getting a separate digital tire gauge.
Also, if you’re topping up your tires, you should do this only when cold, this is because that the pressure will increase as they warm up (nitrogen-filled tires are much more stable), so taking a pressure measurement when they’re hot will always see a high reading.
And then we get to power supply; some of these tire inflators use a 12v DC accessory plug (or cigarette lighter socket), which is handy and convenient, but if the inflator draws too much power, it will trip the fuse for the socket and you’ll be left without power until you’ve replaced the fuse. If you need something a little more heavy-duty, choose an inflator that uses alligator clips direct to the battery.