The consolation for those of us with a seventies birth certificate is that you don’t need to have been around for the Punic Wars to have played with Micro Machines at least once.
And it’s precisely about automobiles—microscopic, in their own way—that we’re talking today.Born in the Land of the Rising Sun, the keijidōsha category (軽自動車)—shortened to kei—is a thoroughly, unmistakably Japanese regulation, dedicated to ultra-compact cars.
The current specs (in force since 1998) set a maximum length of 3.4 meters, a maximum width of 1.48 meters, a maximum height of 2 meters, and an engine displacement of 660 cc.These tiny little rockets, beyond their very particular charm, also come with a whole series of tax perks: from cheaper insurance to significantly reduced annual and weight taxes, with savings that go beyond 30% compared to normal cars.Kei cars were introduced in 1949, with limits of 150 cc (100 cc for 2-stroke engines), which then increased to 360 cc in 1955 and finally to 660 cc in 1990.
The first kei (meaning those that hit the roads between 1949 and 1975) were born as an affordable alternative to motorcycles.
In 1955, iconic models like the Subaru 360 came to life—nicknamed ladybug—and sold in over 392,000 units.Between 1976 and 1990, the era of anti-pollution regulations begins, along with taxes and mandatory inspections, which cause sales to drop considerably.
Still, many models grow in size and get fitted with disc brakes and a whole range of automatisms.From 1990 to 2014, we finally arrive at the infamous 660 cc, with a power cap of ~64 hp, under a strict gentlemen’s agreement among manufacturers—sealed, presumably, with a barrage of bows.
This is where the little sports cars known as gentleman-driver models take hold.Starting in 2009, electric versions also enter the market (spearheaded by the Mitsubishi i-MiEV), and in 2022 the Nissan Sakura EV arrives, with 20 kWh and about 100 km of range.The Subaru 360 (produced between 1958 and 1971) is the first truly successful kei car, with its lightweight body, independent suspension, and a resounding partial exemption from safety regulations.
And it’s precisely about automobiles—microscopic, in their own way—that we’re talking today.Born in the Land of the Rising Sun, the keijidōsha category (軽自動車)—shortened to kei—is a thoroughly, unmistakably Japanese regulation, dedicated to ultra-compact cars.
The current specs (in force since 1998) set a maximum length of 3.4 meters, a maximum width of 1.48 meters, a maximum height of 2 meters, and an engine displacement of 660 cc.These tiny little rockets, beyond their very particular charm, also come with a whole series of tax perks: from cheaper insurance to significantly reduced annual and weight taxes, with savings that go beyond 30% compared to normal cars.Kei cars were introduced in 1949, with limits of 150 cc (100 cc for 2-stroke engines), which then increased to 360 cc in 1955 and finally to 660 cc in 1990.
The first kei (meaning those that hit the roads between 1949 and 1975) were born as an affordable alternative to motorcycles.
In 1955, iconic models like the Subaru 360 came to life—nicknamed ladybug—and sold in over 392,000 units.Between 1976 and 1990, the era of anti-pollution regulations begins, along with taxes and mandatory inspections, which cause sales to drop considerably.
Still, many models grow in size and get fitted with disc brakes and a whole range of automatisms.From 1990 to 2014, we finally arrive at the infamous 660 cc, with a power cap of ~64 hp, under a strict gentlemen’s agreement among manufacturers—sealed, presumably, with a barrage of bows.
This is where the little sports cars known as gentleman-driver models take hold.Starting in 2009, electric versions also enter the market (spearheaded by the Mitsubishi i-MiEV), and in 2022 the Nissan Sakura EV arrives, with 20 kWh and about 100 km of range.The Subaru 360 (produced between 1958 and 1971) is the first truly successful kei car, with its lightweight body, independent suspension, and a resounding partial exemption from safety regulations.
What’s fascinating about these little four-wheeled miracles is the kind of trivia each one hides inside those tiny shells and growling engines.To start with: that “fair play” power cap isn’t actually a law, but rather a gentleman’s agreement among manufacturers, meant to keep 660 cc models at 64 hp—avoiding an otherwise inevitable performance arms race.On top of that, in some rural areas, kei cars don’t even require proof of a parking space, unlike normal cars.Some of the more adventurous models have crossed Japan’s borders to wander the world.
Take the curious case of the Subaru 360, exported to the US as a cheap-and-ugly little runabout—thanks to its shape and despite its questionable safety, to the point of being exempt from routine crash tests.Over the years, truly bizarre variants of the original models have popped up.
There are micro-vans shaped like mini retro-campers, or with a full-on ’60s vibe—like, for instance, “pirate vans” inspired by the VW Microbus.Up until the end of the ’60s, kei two-strokes were fitted with a device called a speed chime: an audible alarm that would kick in whenever you exceeded the speed limit.Just to put it into perspective…
Take the curious case of the Subaru 360, exported to the US as a cheap-and-ugly little runabout—thanks to its shape and despite its questionable safety, to the point of being exempt from routine crash tests.Over the years, truly bizarre variants of the original models have popped up.
There are micro-vans shaped like mini retro-campers, or with a full-on ’60s vibe—like, for instance, “pirate vans” inspired by the VW Microbus.Up until the end of the ’60s, kei two-strokes were fitted with a device called a speed chime: an audible alarm that would kick in whenever you exceeded the speed limit.Just to put it into perspective…
In today’s market, the infamous kei cars no longer meet most of the Euro NCAP standards, and for that very reason they’re hard to export—at least officially—even if some European policies are nudging in the direction of similar urban minicars.Despite everything, kei cars still carry serious weight in Japan’s automotive market, accounting for about 40% of domestic car sales within the minicar segment.
The Daihatsu Move returned in 2025 with its seventh generation, introducing rear sliding doors for the first time on certain trims, bigger touchscreens on those tiny front panels, and a modern interior setup with improved comfort.
The Daihatsu Move returned in 2025 with its seventh generation, introducing rear sliding doors for the first time on certain trims, bigger touchscreens on those tiny front panels, and a modern interior setup with improved comfort.
In this case we’re talking about a kei microvan with compact-minivan traits, but with that distinctive style shared by its other Micro Machines sisters.
The Nissan Sakura, a kei EV launched in 2022, keeps climbing in sales day after day, without slowing down.
There’s a clear push toward EV versions of kei cars. The most famous example remains the Nissan Sakura (EV)—already on the road—while since October 2024, Honda has started selling a micro-electric van classified as kei and designed for urban deliveries, with a stated range that reportedly goes up to around 245 km on a single charge.Basically: a battery on wheels.
There’s a clear push toward EV versions of kei cars. The most famous example remains the Nissan Sakura (EV)—already on the road—while since October 2024, Honda has started selling a micro-electric van classified as kei and designed for urban deliveries, with a stated range that reportedly goes up to around 245 km on a single charge.Basically: a battery on wheels.
BYD—the big Chinese EV brand—is planning to enter Japan’s low-cost kei EV market in the second half of 2026, as a direct response and a thrown-down gauntlet to the traditional Japanese makers.On the other hand, Japan is tightening emissions regulations—both for internal-combustion engines and for periodic inspection eligibility. And with all the politeness our brothers from the Land of the Rising Sun are known for, it has to be said: not all aftermarket modifications are viewed kindly, let alone properly regulated. Even kei EVs come with their own set of questions—how to charge them, how to maintain batteries, how to handle charging infrastructure in cities and out in rural areas.So-called super-height wagons (i.e., very tall, with vertical interiors and a big emphasis on space efficiency) have always been among the most popular kei models—especially those with sliding doors and practical configurations that make them particularly appealing to families, delivery services, and urban use in general.
By now, you can also see growing demand for “premium within kei” models: nicer finishes, cutting-edge tech—like digital infotainment and driver assistance—that deliver higher comfort and, in a way, justify a relatively high price for a kei.Even for the little sisters of traditional cars, customization reigns supreme. It even includes SUV-style kei cars (micro crossovers), two-tone paint jobs, and aesthetic details made solely to stand out—despite the modest size limits.
By now, you can also see growing demand for “premium within kei” models: nicer finishes, cutting-edge tech—like digital infotainment and driver assistance—that deliver higher comfort and, in a way, justify a relatively high price for a kei.Even for the little sisters of traditional cars, customization reigns supreme. It even includes SUV-style kei cars (micro crossovers), two-tone paint jobs, and aesthetic details made solely to stand out—despite the modest size limits.
The American market for imported kei trucks/kei cars keeps growing steadily, especially thanks to the 25-Year Import Rule, which allows imports of vehicles that are properly “ultra-adult”—specifically, over 25 years old—neatly bypassing certain federal standards.
That said, various states are dealing with restrictions: in some cases, these vehicles can’t be registered for road use, or they run into limits on access to certain types of roads.Some recent laws do recognize kei as an allowed category. For instance, in Colorado a law was approved that defines what counts as a kei vehicle eligible for registration—provided it meets certain rules on dimensions, power, and safety requirements such as front-impact airbags, passing crash tests, emissions limits, and homologations that are rather costly and often more complex than for non-original vehicles, or even modified ones.Either way, import costs, aftermarket parts, duties and customs—also factoring in shipping and delivery for our little rocket—can make getting one of these gems at least not very convenient, if it isn’t planned properly.And still: in an era when the automobile is increasingly synonymous with gigantic SUVs and overweight crossovers, Japan keeps proudly cultivating this contrarian niche. These small kei cars—light and compact—born from postwar engineering minds as an economical answer to national mobility needs, are today a cultural and industrial phenomenon, unquestionably unique in the world.
That said, various states are dealing with restrictions: in some cases, these vehicles can’t be registered for road use, or they run into limits on access to certain types of roads.Some recent laws do recognize kei as an allowed category. For instance, in Colorado a law was approved that defines what counts as a kei vehicle eligible for registration—provided it meets certain rules on dimensions, power, and safety requirements such as front-impact airbags, passing crash tests, emissions limits, and homologations that are rather costly and often more complex than for non-original vehicles, or even modified ones.Either way, import costs, aftermarket parts, duties and customs—also factoring in shipping and delivery for our little rocket—can make getting one of these gems at least not very convenient, if it isn’t planned properly.And still: in an era when the automobile is increasingly synonymous with gigantic SUVs and overweight crossovers, Japan keeps proudly cultivating this contrarian niche. These small kei cars—light and compact—born from postwar engineering minds as an economical answer to national mobility needs, are today a cultural and industrial phenomenon, unquestionably unique in the world.
