Solving the Second Layer (Middle Layer) of a Rubik's Cube
Published by System Administrator
Understanding the Middle Layer
After completing the first layer (white cross plus four white corners on the bottom), the next challenge is solving the middle layer — also known as the second layer or E layer. This layer contains four edge pieces that sit between the first layer and the last layer. These edges do not have any yellow stickers (assuming yellow is opposite white), so you can identify them by looking at the top layer for edges that have no yellow.
The four middle-layer edges connect adjacent face centers. For example, the red-blue edge sits between the red center and the blue center. Your goal is to insert each of these four edges from the top layer into their correct middle-layer slot with the correct orientation.
Finding Middle Layer Edges
Hold the cube with the white face on the bottom (the solved first layer). Look at the edges in the top layer. Each edge in the U layer has two colors. If neither color is yellow, that edge belongs in the middle layer. If one color is yellow, leave it alone — it belongs in the last layer and will be solved later.
To begin, find a middle-layer edge in the top layer. Rotate U until the front sticker of that edge matches the center color of the face it's on. For example, if you see a red-blue edge with the red sticker facing you, rotate U until that edge is on the red face (the red sticker aligns with the red center).
Algorithm 1: Insert Edge to the Right
If the edge's second color matches the center to the right (e.g., red is facing you and blue is on the right), use this algorithm to insert the edge to the right:
U R U' R' U' F' U F
This 8-move sequence lifts the target slot, positions the edge, and drops everything into place. Break it down into two parts: "U R U' R'" moves the edge away while opening the slot, and "U' F' U F" inserts the edge and closes the slot. Practice each half separately, then combine them.
Algorithm 2: Insert Edge to the Left
If the edge's second color matches the center to the left (e.g., red is facing you and green is on the left), use the mirror algorithm to insert the edge to the left:
U' L' U L U F U' F'
This is the mirror image of Algorithm 1. It opens the left slot, positions the edge, and inserts it. You'll notice it uses L and F moves instead of R and F moves, with the U direction reversed.
What If the Edge Is Already in the Middle Layer?
Sometimes a middle-layer edge is already in its correct slot but flipped (the colors are swapped), or it's in the wrong slot entirely. In both cases, you need to extract it first before reinserting it correctly.
To extract a middle-layer edge, position the misplaced edge at the front-right slot and perform Algorithm 1 (U R U' R' U' F' U F). This will push a random top-layer edge into the slot while popping the middle-layer edge out to the top. The extracted edge may not immediately be over its correct slot, so rotate U to position it and then insert it using the appropriate algorithm.
Common Mistakes to Avoid
- Wrong alignment: Always align the front color with its center before choosing which algorithm to use. If you skip this step, the edge will go into the wrong slot.
- Using the wrong algorithm: Carefully check whether the second color matches the right or left center. Using Algorithm 1 when you need Algorithm 2 (or vice versa) will place the edge in the wrong position and you'll have to extract and redo it.
- Forgetting edge orientation: Even if an edge is in the correct slot, it might be flipped. A flipped edge must be extracted and reinserted.
Practice Strategy
Once you can reliably solve the middle layer, practice combining the first and second layers into one fluid phase. The transition should be seamless — as you insert the last first-layer corner, immediately look for middle-layer edges. Reducing pause time between steps is one of the easiest ways to cut seconds from your solve time. Aim to complete the first two layers in under 40 seconds before moving on to learn the last layer.