Servo Motor 180° vs 270° vs 360°: Which Do You Need?

A 180° servo moves to the angle you command and holds it; a 360° (continuous) servo cannot hold an angle at all — its write() value controls speed and direction instead. A 270° servo is simply a positional servo with a wider sweep. All three look identical from the outside, so below is a 30-second sketch to tell them apart.

Why do 180°, 270° and 360° servos look exactly the same?

Because the case, the three-wire lead and very often the product name are identical — only the variant differs. “Servo motor 180 vs 360 — what’s the difference?” is the single most common servo question our support team handles, and it regularly turns into “wrong item” complaints where the servo was actually behaving exactly as designed.

The difference is entirely internal. A positional servo (180° or 270°) can find and hold a commanded angle. A continuous-rotation servo has that ability removed — it behaves like a gear motor with a servo plug. You cannot tell them apart by looking; you tell them apart by testing.

What is the real difference between a 180°, 270° and 360° servo?

Everything comes down to what write() does inside the servo. Here is the whole story in one table.

Behaviour	180° servo	270° servo	360° continuous servo
Type	Positional	Positional, wider range	Not positional (continuous rotation)
What write(angle) does	Moves to that angle (0–180) and holds it	Moves to a point mapped across the wider 270° sweep and holds it	Sets speed and direction: ≈90 = stop, toward 0 = full speed one way, toward 180 = full speed the other
Can it hold a commanded angle?	Yes	Yes	No — it keeps rotating
Typical projects	RC steering, robot arm joints, camera pan	Same jobs as 180°, when you need a wider sweep	Wheels, winches, pulling a line
Think of it as	A dial you point	A dial with more travel	A gear motor with a servo plug

So a 360° servo is not an “upgraded” 180° — it is a different tool. If your project needs the horn to stop at a specific angle, a continuous servo can never do it.

How do I test which servo I actually have?

Upload this sketch, power the servo, and watch what happens. It commands the 90° centre position — the one value where the two servo families behave completely differently.

// Servo identification test - Arduino Uno/Nano
// Positional (180/270): moves to centre and HOLDS firm.
// Continuous (360): STOPS, or creeps slowly.
#include <Servo.h>

Servo testServo;

void setup() {
  testServo.attach(9);   // orange/yellow signal wire to pin 9
  testServo.write(90);   // command the 90-degree centre position
}

void loop() {
  // Nothing to do here - just watch the servo:
  // Swings to the middle and holds      = positional (180 or 270)
  // Sits still, or drifts very slowly   = continuous 360
}

If a continuous servo drifts slightly at 90 instead of stopping dead, gently turn the small trim potentiometer on the servo body (if present) until it sits still. That is calibration, not a defect.

Which servo do you actually need?

Choose 180° or 270° when you need position

RC steering, robot arm joints and camera pan brackets all need the servo to go to an angle and stay there — that is positional territory, so pick the SG90 180° micro servo for light mechanisms. Reach for 270° only when 180° of travel is not enough.

Our jemuran automatik with rain sensor tutorial is a good worked example of servo control in a real Malaysian project.

Choose 360° continuous when you need rotation

Robot wheels, winches and anything that pulls a line want continuous rotation — that is the SG90 360° continuous servo. Remember the control logic flips: you are commanding speed, not angle.

// Continuous (360) servo demo - write() = speed + direction
#include <Servo.h>

Servo wheel;

void setup() {
  wheel.attach(9);
}

void loop() {
  wheel.write(0);     // full speed in one direction
  delay(2000);
  wheel.write(90);    // about 90 = stop
  delay(1000);
  wheel.write(180);   // full speed the other direction
  delay(2000);
  wheel.write(90);    // stop again
  delay(1000);
}

SG90 or MG996R? Pick by load, not by looks

The SG90 is a 9g micro servo with plastic gears, made for light loads — sensor brackets, small linkages, school RBT projects. The MG996R has metal gears and much higher torque, which is what you want for heavier robot arms. If the mechanism feels heavy in your hand, the SG90’s plastic gears are the part that will complain first.

How do you wire and power a servo correctly?

All three servo types share the same three-wire hobby connector, so the wiring never changes — only the code does.

Wire colour	Connects to	Note
Brown / black	GND	Must be shared with the Arduino GND
Red	5V supply	Use a proper 5V source under load, not the Arduino 5V pin
Orange / yellow	Signal	Any digital pin — Servo.h does not need a hardware-PWM pin. Pin 9 is just the classic choice

The power line matters more than beginners expect. Under load, a servo fed from the Arduino’s 5V pin causes jitter and random board resets — power it from a dedicated 5V supply and share only the ground. An adjustable module dialled in does this well; see our guide on adjusting an LM2596 buck converter to 5V.

Common mistakes we see from real customers

“Mcm mana nak beza servo motor 180° dan 360° eh, sbb nama dua-dua sama ja yang saya terima” — Correct observation: the printed name is often identical, and the case gives nothing away. The fix is the 90° test sketch above. Positional holds the centre; continuous stops or creeps. Thirty seconds and you know.

“If I need to use a servo for RC, which one?” — For RC steering you need positional control, so 180° (or 270° if you want a wider sweep). A continuous servo on a steering linkage would just keep spinning past centre — save the 360° for drive wheels and winches.

One customer was sure we had shipped the wrong item: their “180° servo” just kept rotating and never held an angle. It was a continuous-rotation variant doing exactly what it was designed to do — the order simply had the other variant selected. Before opening a dispute, check the variant on your order and run the test sketch; the servo is usually innocent.

FAQ

How do I tell a 180° and a 360° servo apart without a label?

Run a sketch that commands write(90). A positional servo swings to centre and holds firm; a continuous servo stops still or drifts slowly. That single test settles it.

Can a 360° continuous servo hold a position?

No. Its write() value only sets speed and direction, so it physically cannot park at a commanded angle. If your project needs a held angle, use a 180° or 270° positional servo.

Which servo should I use for RC steering?

A positional one — 180° for most builds, 270° if the mechanism needs a wider sweep. Continuous servos are for wheels and winches, not steering.

Why does my servo jitter or my Arduino keep resetting?

Almost always power. A loaded servo drawing from the Arduino’s 5V pin causes exactly these symptoms. Feed it from a proper external 5V supply and connect the grounds together.

Do I code a 270° servo differently from a 180°?

Same Servo.h, same write() calls. The difference is that the command range is mapped across the wider 270° sweep, so each step of write() covers more physical travel.

Last updated July 2026. Stuck? Chat with us on WhatsApp.