What Is Blindtrainer?

Blindtrainer is a free, browser-based training tool for Rubik's Cube blindfolded solving. It is built around drilling commutators and algorithms — primarily 3-style — for corners, edges, wings, centers, and parity cases. You pick a case set, work through cases one at a time, and the site tracks your streak, total cases trained, time spent, and your best single-day volume. If you already solve blindfolded and want structured repetition instead of scrolling through a spreadsheet of algs, this is the tool's purpose.

What you can practice

The trainer organizes practice into case sets rather than one undifferentiated pool. From the site:

The mix covers the standard 3-style territory plus the "floating" buffer variants that more advanced solvers use to avoid fixed-buffer bottlenecks. If you are still on a single fixed buffer, the core corner and edge sets are the natural starting point; the floating and center sets matter once you are pushing into big-cube blindfolded or optimizing your buffer choices.

How a practice session works

1. Choose a case set (for example, Corners or Wings).
2. The trainer presents cases for you to solve.
3. Solve each one using your commutator or algorithm.
4. The site records the attempt and moves you to the next case.

Alongside the case display, the interface keeps a running Streak, Total cases trained, Time spent training, and Most cases trained in 1 day. Those four numbers are your feedback loop — they tell you whether you are actually putting in volume or just opening the page.

Customization and data

• Accent Color — visual preference only.
• Speffz / Custom — choose the standard Speffz lettering scheme or define your own. The custom option exposes the full sticker list (UBL, UBR, UFR, UFL, LUB, LUF, LDF, LDB, FUL, FUR, FDR, FDL, RUF, RUB, RDB, RFD, BUR, BUL, BDL, BDR, DFL, DFR, DBR, DBL, UB, UR, UF, UL, LU, LF, LD, LB, FU, FR, FD, FL, RU, RB, RD, RF, BU, BL, BD, BR, DF, DR, DB, DL), so you can remap letters to match however you actually read the cube.
• Slow Cases — isolates the cases you are slowest on, so you can drill weaknesses instead of re-solving what you already know.
• Hard Reset — wipes progress. Use it deliberately; there is no undo described.
• Sync Data / Import / Export / Your ID — progress can be tied to an ID and moved between sessions or devices via import and export. If you train on more than one machine, set up the ID before you accumulate a long streak.

Cost and how it stays online

The site states it is 100% free and asks for donations to cover maintenance costs and fund regular updates. Donation routes listed are PayPal ([email protected]) and a bank account (AT16 3306 5000 0197 2785). There is no paywall, account tier, or feature lock described — the donation ask is explicitly framed as keeping the site free, not as unlocking content.

Who it is for

• Useful if you already know 3-style commutators and want volume-based drilling with stats, custom lettering, and a slow-case filter.
• Less useful if you are still learning what a commutator is — the trainer assumes you can execute the case, not that it teaches the method.
• Worth trying if you use floating buffers or solve big cubes blindfolded, since the floating and center sets are unusual to find in one free tool.

The practical test: pick your main case set, run a session, and check whether the streak and slow-case data change how you practice. If they do, the tool is doing its job.