EC11 vs EC12 Rotary Encoders: Which One for Your Design?
EC11 and EC12 are the two most common sizes of incremental rotary encoder: EC11 has an 11 mm body, EC12 a 12 mm one. The extra millimeter on the EC12 usually buys a slightly firmer feel and a common 24-pulse, 24-detent configuration, while the EC11 is the smaller, more widely stocked default for cost-sensitive volume designs.
Both EC11 and EC12 do the same job: they report shaft rotation as two out-of-phase pulse trains for volume, menu and setting controls, and both usually offer an integrated push switch for press-to-select. The names describe the body size, not one vendor’s part, so many manufacturers build to the EC11 and EC12 form factors. What differs in practice is size, the usual pulse-and-detent count, and availability. The EC11 at 11 mm is the default for cost-sensitive volume; the EC12 at 12 mm, often written as 24P24C, gives a defined 24-step feel. Swiclick builds both, the GE11 to the EC11 standard and the GE12 to the EC12 standard, so an existing design can be second-sourced to either without changing the footprint it was built around.
The practical differences
Size comes first: 11 mm against 12 mm decides how much board and panel room the encoder takes and how large a knob sits on top. Resolution and detent come next: an EC11 is built in several pulse-and-detent counts, commonly 15, 20 or 24, while an EC12 is most often the 24-pulse, 24-detent part. Both are offered in through-hole and surface-mount versions, with a 5-pin layout when the push switch is included. Availability tilts toward the EC11, which is stocked in higher volume across the industry, so it usually wins on cost and lead time when its configuration fits.
When to choose EC11
Reach for the EC11 when board space is tight, the design is cost-sensitive or high-volume, and a standard pulse-and-detent count does the job. It is the smaller, more widely available default, and for most volume controls and menu dials it is enough.
When to choose EC12
Reach for the EC12 when you want the defined 24-step feel of a 24P24C part and the extra millimeter of body fits. The slightly larger frame can feel a little firmer under a bigger knob, which suits front-panel controls where the turn should feel deliberate.
Second-sourcing an EC11 or EC12
The two are not drop-in for each other; the body size and footprint differ, so a swap is a design decision, not a like-for-like part change. When you second-source either one, line up the pulses per revolution, detent count, shaft form and length, mounting style, and whether a push switch is present, against the part you are replacing. Read the pulse-and-detent count from the part-number suffix rather than the body size, since two 11 mm encoders can be a 15-detent and a 24-detent part. And if a design shrinks past both, a miniature rotary encoder does the same job in a 4.8 x 3.8 mm surface-mount body. Swiclick’s GE11 and GE12 are built to the EC11 and EC12 standards as an independent alternative, not affiliated with any other encoder brand; send the encoder you use and our engineers will match it and share the specs.
FAQ
Neither is better on its own. The EC11 wins on size, cost and availability; the EC12 wins when you want a defined 24-step feel and can fit the slightly larger body. The load is the design, not the label.
It means 24 pulses and 24 detents per revolution: 24 defined steps you can feel, each producing one pulse. It is the common configuration for the EC12.
No. They differ in body size and footprint, so one is not a drop-in for the other. Check the footprint and configuration before treating a swap as like-for-like.
Many EC11 encoders include an integrated push switch, usually as a 5-pin part, for press-to-select. Confirm it on the specific configuration.
Talk to an engineer
Tell us your application and the specs you need, and our engineers will match a Swiclick switch and share its datasheet and pinout. Free samples ship 1 to 50 for validation before volume.
Written by Eric Chen, Application Engineer, Swiclick.
