An offline speedcubing trainer for the 3×3 and the 2×2, from a first solve to a fast average — a timer, beginner's guides and an algorithm trainer for CFOP and Roux on the 3×3 and Ortega on the 2×2, and a guide and phase timing for ZZ. It runs in the browser and installs as an app on a phone or a computer: rubix.lahvi.cz
Free, no account, no ads. Once opened, it works without a connection. English and Czech.
- The 3×3 or the 2×2, switched in the header's corner; everything else — the sessions, the statistics, the guide, the trainer — follows the cube you pick.
- Hold to start (space bar or anywhere on the screen), tap anything to stop.
- WCA inspection with a countdown bar and beeps at 8 and 12 seconds; going over gives the +2 or DNF on its own.
- Random-state WCA scrambles generated on the device, with a flat or 3D preview of the scrambled cube. Paste your own scramble to practise a particular situation.
- While the clock runs, only the time is on screen — and you choose whether it shows hundredths, tenths, whole seconds or nothing at all.
- Under your averages, what the next solve needs for a new best ao5 or ao12 — shown only while one is in reach, and it can be turned off.
- Every solve with its scramble, penalty, tags, note and star; fix a mistyped time or a penalty later.
- Separate sessions for different practice, each timed in CFOP, Roux or ZZ on the 3×3, archived when you are done with them. Each cube keeps its own sessions, personal bests and goal.
- Deleting a solve can be undone for a few seconds.
- Current and best ao5, ao12, ao50 and ao100, personal bests, mean, median, standard deviation, DNF and +2 rate.
- A histogram of times, and a trend of the rolling ao12 against the slower ao50, with every single from the second solve on.
- Averages follow the csTimer convention, so the numbers match what you are used to.
- With sessions in more than one method, the statistics across sessions read one method at a time, and each method keeps its own personal best.
- CFOP: PLL, OLL and F2L — with two further levels of F2L for a pair that starts in the wrong slot — plus 2-Look OLL and PLL for the way most people learn them.
- Roux: the second block's 65 pairs, CMLL — all 42 cases, with 2-Look CMLL on the way there — the eleven cases of edge orientation, and EOLR, which orients the edges and places the side ones in a single algorithm.
- 2×2: Ortega's seven OLL cases and five PBL cases.
- Every case drawn as a diagram, with arrows for where the pieces go; play the algorithm on a 3D cube move by move, in your own colour scheme.
- Alternative algorithms for a case — left-handed ones marked as such — your own algorithms, and named triggers (sexy move, sledgehammer…) highlighted inside them.
- Mark each case as new, learning or known, and see how far through a set you are.
- Drill a chosen set of cases against the clock, from a real scramble into the case, and see which ones are your slowest; or drill recognition alone, naming the case you are shown. The cross has a drill of its own.
- Time each phase by tapping as you finish it: cross, F2L, OLL and PLL in CFOP, the two blocks, CMLL and the last six edges in Roux, EOCross, F2L and the last layer in ZZ.
- See your average and best time for every phase, how your current ao12 divides between them, and how they change over time.
- A whole first solve in seven steps, with pictures of how to hold the cube — for CFOP, or for Roux with its blocks built by feel, only two algorithms and a picture for every way its last edges can lie.
- A guide to ZZ for a cube you can already solve: how to tell a bad edge from a good one, how to turn them all good, and the cross and pairs that follow.
- The 2×2 layer by layer in three steps, with four moves and one algorithm to learn — and Ortega, the quicker way: a face, then the top and both layers with twelve algorithms.
- Each cube's guide can be hidden once you no longer need it.
- Send a solve or an average as a picture.
- Send a link with the same scrambles, so a friend can try to beat your time or your ao5.
- Back up everything to a single file and restore it, or merge it into another device; you see what will change before anything does.
- Import your history from csTimer.
- Export solves to CSV for a spreadsheet.
- Light and dark theme, cube colour schemes, text and clock size, a choice of fonts.
There are no accounts and no backend. Everything you record stays in your browser's storage and leaves the device only when you export it yourself. The one outside request is Cloudflare Web Analytics, which counts page views; it knows nothing about your solves and nothing waits for it.
Most of the CFOP algorithms are from J Perm, and the 3×3 beginner method follows badmephisto. The 2×2 — its beginner method, Ortega and its algorithms — is J Perm's too. The Roux sets come from the sheets of Kian Mansour and the Roux community; the second-block cases those sheets leave out are from SpeedCubeDB. The ZZ guide follows the tutorial by crystalcuber and the ZZMethod.com team. Every algorithm in the app is checked by running it on a model of the cube before it ships.
Open an issue — or, without a GitHub account, write to the e-mail on the app's About screen. More in CONTRIBUTING.md.
Node 24 (see .node-version).
npm install
npm run dev # development server, no service worker
npm test
npm run build && npm run preview # the real PWA, with offline cachingA push to main builds and deploys to Cloudflare Workers as static assets.
Rubix is my project. The idea, what goes in and what stays out, how every screen behaves and looks — those are my decisions, and I try the changes with a cube in my hands on real devices.
I write the code together with Claude Code,
Anthropic's AI coding assistant; the commits it worked on say so in their
Co-Authored-By line.
Built with Vite, React and TypeScript, Dexie over IndexedDB, cubing.js for scrambles and 3D playback and Recharts for charts. The specification (SPEC.md) and the project conventions (CLAUDE.md) are in Czech; the code, comments and commit messages are in English.
GPL-3.0-or-later. You may use, change and share Rubix; a changed version you distribute has to stay open under the same license.