Bike-share, no doubt, is going to be a major addition to the streets of New York — in terms of both impact and visibility. Within the service area, there’s going to be a station every few blocks. And some of those stations are going to have a lot of bicycle docks: 59 in many locations, and a whopping 118 next to Grand Central. Thanks to the small footprint of bikes, however, overall this new form of transit will consume relatively little space while allowing people to make tens of thousands of trips per day.

Much of the discussion of bike-share’s size involves the number of parking spots the system will displace, and with the release of the draft service area map last week, it’s possible to estimate how much car parking will give way to bike-share stations. (“How Many Parking Spaces Will CitiBike Share Gobble Up?” went the Gothamist headline yesterday.) But some perspective is in order: Only a fraction of the proposed bike-share stations will remove parking spaces, and those are clustered in neighborhoods where community boards specifically requested that the docks stay off their already-crowded sidewalks.

Of the 420 stations scheduled to open this year, only 157 replace car parking — a little more than one in three. (To run the numbers we used Gothamist’s spreadsheet of Manhattan bike-share locations and added our own count of stations in Brooklyn and Queens slated to replace parking. You can download Streetsblog’s spreadsheet with that information and all the math in this post.) Most bike-share stations are slated for on-street locations that don’t take away parking, on sidewalks, in parks and public plazas, or on private property. That 118-dock station near Grand Central, for example, will be in a no-parking zone of Park Avenue.

More importantly, the bike-share system will provide far more total transportation capacity in that curbside space than automobile parking does. Bike-share will eliminate 623 on-street parking spaces, according to Streetsblog calculations (one parallel parking space takes up around 22 feet of curbside space; bike-share can fit four docks — or three docks and a payment kiosk — in ten feet). In those spots will be 5,320 new bike-share parking spaces: eight and a half times as many.

To put it differently, you could fit a 39-dock station in just five parking spaces. Bikes are simply a lot smaller than automobiles, and the space it takes to store one car can hold a lot more bikes.

The rate of turnover gives bike-share another big advantage over car parking.

The cost structure of bike-share ensures a regular stream of bikes in and out of every station. In Washington D.C.’s bike-share system, the average bike is ridden 3.5 times a day. New York City’s larger and denser system is expected to be more heavily used. Parked cars, in contrast, can sit for days at a time in New York’s millions of unmetered spaces.

Now, for that set of New Yorkers who currently drive, would never try out bike-share, and don’t care that their neighbors have a new way of getting around, it’s true that bike-share will take away a few parking spaces. But these same New Yorkers are losing far more curbside space to other factors compared to bike-share.

In 2011 alone, there were 3,231 new curb cuts built in New York City, according to the Department of Buildings. Each of those curb cuts eliminates a curbside parking space. In many cases, this is nothing more than homeowner privatization of public parking: a curb-cut leading to a one-car driveway removes one space from the public parking supply and gives it to a private landowner. Over the last five years, 23,760 new curb cuts have been built. Compared to that torrent of curbside parking loss, bike-share is a drop in the bucket.

Alternatively, compare the amount of parking spaces re-purposed for bike-share to the number eaten up by placard holders. Right now, there are 78,000 official parking placards in circulation. At any given time, a sizable share of those are being used improperly, while some large but unknowable number of bogus placards are also being displayed on dashboards. In a one-day survey of just five small neighborhoods, Transportation Alternatives found more parking spaces filled by cars illegally using placards, 820, than would be displaced by bike-share citywide.

Bike-share is a big deal and New Yorkers are certainly going to notice its arrival. But it’s hardly going to be a dramatic change in the amount of available parking, and where it does subtract space for car parking, it adds eight times as many spaces for bike parking.