Rubik's Cube Solver
Blog Article • Jul 20, 2025

How to Get Sub-20: A Comprehensive Speedcubing Guide

Published by System Administrator

The Sub-20 Challenge

Sub-20 is widely considered the gateway to serious speedcubing. At this level, you're faster than approximately 90% of all cubers, and your solves demonstrate genuine skill in every phase of the CFOP method. Reaching sub-20 typically takes 6-12 months of focused practice from the point of first learning CFOP, and requires systematic improvement across all four stages of the solve.

Unlike earlier milestones (sub-60, sub-30), where improving one skill can produce dramatic results, sub-20 demands competence in everything. A weak cross can be compensated by fast F2L at the sub-30 level, but at sub-20, every phase must be reasonably optimized.

Cross: Under 2 Seconds, Every Time

Your cross should be fully planned during inspection and executed in under 2 seconds. At sub-20 level, you should be planning all 4 edges and choosing the best starting color (if you're dual color neutral) or the best edge insertion order (if white-only). Target cross move count: 6-7 moves average.

Advanced cross techniques for sub-20 include: using D-layer adjustments instead of U-layer setups, planning the first F2L pair alongside the cross (pseudo X-cross), and recognizing when an unconventional cross solve order saves moves by exploiting piece adjacency.

F2L: 7-9 Seconds Total

F2L is the single largest time component of a sub-20 solve. Your target is 7-9 seconds for all four pairs. This requires:

  • Intuitive F2L mastery: You should know multiple solutions for every F2L case and instinctively choose the most efficient one based on empty slot availability and pair positioning.
  • Consistent lookahead: No pauses longer than 0.3 seconds between pairs. Your eyes should always be scanning for the next pair while your hands complete the current one.
  • Minimal rotations: Average no more than 2 whole-cube rotations per solve. Learn to insert pairs from the back using mirror algorithms instead of rotating to see the front.
  • Efficient solutions: Average 8-9 moves per pair (32-36 total F2L moves). If your F2L averages more than 40 moves, you're using suboptimal solutions.

OLL: Full OLL or Optimized 2-Look

You can reach sub-20 with 2-look OLL, but learning full OLL (57 algorithms) gives you a 1-2 second advantage. If you choose to stay with 2-look, ensure your edge orientation step is under 1 second and your corner orientation step is under 2 seconds, with recognition under 0.5 seconds for both.

Priority OLL algorithms to learn first (if transitioning from 2-look): the dot cases, P-shapes, and W-shape cases, as these are the most common and have the most time-saving potential.

PLL: Full PLL Required

All 21 PLL algorithms should be learned and drilled. Your average PLL execution time should be under 2 seconds including recognition. The most impactful PLLs to optimize are: Ua/Ub (most common), T-perm, Y-perm, and Jb-perm.

For each PLL, practice both the algorithm execution and the recognition. Recognition means identifying which PLL case you have by looking at the side patterns. Fast recognition saves 0.3-0.5 seconds compared to slow, deliberate case identification.

Training Schedule for Sub-20

Structured daily practice (30-45 minutes minimum):

  1. Cross drills (5 min): 10 scrambles, plan cross completely, execute with eyes closed. Target: 90%+ success rate.
  2. Slow F2L (10 min): Untimed solves at 50% speed, focusing purely on lookahead continuity. No pauses allowed.
  3. Algorithm drilling (10 min): Drill your weakest OLL and PLL algorithms 30-50 times each.
  4. Timed solves (15-20 min): Full solves tracking Ao12 and Ao100. Analyze your worst solves to identify which phase caused the slow time.

Common Sub-20 Plateaus

If you're stuck around 20-22 seconds, the problem is almost always one of these: excessive F2L rotations (filming yourself solves reveals this), slow OLL/PLL recognition (practice recognition without execution), or inconsistent cross (track cross time separately using split timing). Identify your specific weakness and target it with dedicated practice rather than doing random solves hoping to improve.