
From the driver's position, observe the wiper on the front windshield of the car. When the raised part of the wiper just aligns with the right edge line of the road outside, the distance between the car body and the roadside is approximately 30cm. When observing from the driver's seat, if about 1/3 of the right side of the car's front aligns with the right edge line of the road outside, the distance between the car body and the roadside is just about 30cm. By observing through the right side mirror, when the outermost point of the front right door handle is tangent to the edge of the road outside, the distance between the car body and the roadside is exactly 30cm.

















When I first started learning to drive, I found it particularly challenging to keep the car 30 centimeters away from the curb during parallel parking. My instructor taught me to first align the car with the one in front, keeping a door's width distance, then look at the right rearview mirror while reversing. The moment the curb line appears in the mirror, remember that point and keep the car body a fist's width away from the line. Reverse slowly, make slight steering adjustments, don’t rush, and avoid getting the front too close inside. After several attempts, I found using the car's midline or rear wheel position as reference points worked better. Keeping 30 centimeters is tricky—too close risks scraping the curb, too far is illegal parking, so practice is key to getting the feel. Time yourself with a or find an empty lot to practice repeatedly, and remember to step out and check the distance—practice makes perfect. New drivers shouldn’t panic; play some relaxing music, control the speed, and it’ll soon become second nature.

After driving for over a decade, maintaining a 30cm distance during parallel parking is no longer stressful for me. My method involves checking the angle between the rear window and the roadside line before reversing. A 30cm gap roughly corresponds to the distance from the outer edge of the car body when the wheel aligns with the line in the rearview mirror. During reversing, I gently press the brake and gradually turn the steering wheel to the right, straightening it when I sense the rear wheel is about to touch the curb. If the line isn't clear, I use shadows from streetlights or tree trunks as references, or even the edge of the dashboard inside the car as an auxiliary point. Don't solely on mirrors; step out frequently to check the distance—experience comes with practice. Street parking often involves uneven surfaces, so pay attention to the car's posture and prioritize safety. Whether driving an electric or manual car, maintain steadiness; excessive speed leads to greater errors. I once scraped a tire against the curb, reminding myself to take it slower next time.

Back when my friend was teaching me to drive, we often discussed the details of parallel parking. The most reliable way to maintain a 30cm distance from the curb is to align reference points on your car—such as the wheel center or the bottom edge of the side mirror—with the roadside line, while reversing slowly without turning the steering wheel too sharply. Precise steering control is key, with minor adjustments of just a few centimeters forward or backward. Beginners often make mistakes by reversing too quickly or choosing inconsistent reference points, so I recommend practicing in an empty parking space and using stickers to mark distances as memory aids. The 30cm standard helps avoid fines and prevents scrapes, but don’t rigidly stick to the number—adjust flexibly based on road conditions. In rain or at night when lines may be unclear, I use my ’s flashlight to check, repeating the process until muscle memory kicks in, making parking smooth and effortless over time.

As I've gotten older, my eyesight isn't what it used to be, but I still insist on parking myself. For parallel parking with a 30cm alignment, I on a simple method: stop completely before reversing, glance at the rear window from the driver's seat to estimate the distance between the curb and the wheels - 30cm feels like slightly more than the length of an arm. Maintain a steady rhythm while reversing, turn the steering wheel slightly, and stop immediately to straighten the wheels when you hear a sound or feel vibrations indicating the rear wheels are close to the curb. I've added auxiliary mirrors on the car corners to better see the distance - safety first, no risks. In the city, parking lines are often blocked, so observe surrounding vehicle distances in advance. With practice, intuition will guide you. Remember: slow down, step out to check more often, practice makes perfect, and avoid fines or wheel rim damage.

Last time at the supermarket parking lot while teaching my daughter to park, we discussed how to align with the 30cm line. I said first determine the curb position through the rearview mirror. When reversing at an angle, maintain a palm-width gap after the line appears in the mirror. Make slight steering adjustments to control the angle—don't rush the reverse. Stop before the rear wheels touch the curb and measure the distance. During practice, find a quiet spot and mark reference lines on the ground for spacing. Repeat trial and error to develop the feel. The 30cm standard isn't just compliant—it protects the car body (too close risks scraping, too far wastes space). Broadly speaking, urban parking lanes are narrow, so reference points vary by driver. With experience, you'll handle all road conditions effortlessly.


