Binary Finger Counting Quiz

BitReach is a free browser quiz for learning how ten fingers can represent binary values from zero through 1,023. The practice works in both directions. In Build mode, a decimal target appears and you raise the on-screen fingers whose place values make that number. In Read mode, a hand gesture appears and you enter its decimal value. Mixed sessions alternate those tasks so recognition and construction develop together. The game needs no camera, download, account, or payment.

Choose a five-bit 0–31 starter range, an eight-bit 0–255 range, or the full ten-bit 0–1023 challenge. Every active finger is a native button with a visible weight and pressed state. Touch players can tap. Keyboard players can focus the board, use number keys 1 through 0 to toggle the ten positions, and press Enter to check or advance. The same complete start, multi-question, result, and replay flow fits a 390 CSS-pixel viewport.

How binary finger counting works

A binary digit, or bit, has two states: zero and one. BitReach maps lowered fingers to zero and raised fingers to one. The rightmost low bit is worth 1. Each move to the left doubles the place value through 2, 4, 8, 16, 32, 64, 128, 256, and 512. Add the weights of raised fingers to get the displayed decimal number. All fingers down equals zero. All ten fingers raised equals 512 + 256 + 128 + 64 + 32 + 16 + 8 + 4 + 2 + 1, or 1,023.

The labels shown in the game are authoritative because real-world finger-counting conventions can assign hands or directions differently. This implementation keeps one stable visual order and never asks a camera to infer a pose. The educational task is place-value practice, not gesture recognition.

Two practice directions in one short session

Recognizing a displayed pattern is not the same as constructing a pattern from a number. Mixed mode deliberately alternates those skills across eight questions. Build questions show a decimal target and a live binary readout for the selected on-screen fingers. Read questions lock the displayed fingers and provide a labelled numeric field. Players who want focused repetition can choose only Build or only Read before starting.

The optional timer provides 75 seconds for the run. Untimed practice leaves the clock out of the decision. Either setting reaches a result screen with correct answers, lifetime local totals, and replay controls. A timed run can also finish when time expires instead of inventing unanswered questions as wrong results.

Per-bit explanations instead of a single red X

After each submission, BitReach compares every active place value. If a required bit is missing, the explanation names that weight and says to raise it. If an extra bit is present, the explanation says that weight does not belong in the target. Correct positions remain visible alongside mistakes, so a learner can identify the exact difference between the submitted and target patterns before continuing.

A small adaptive counter increases review priority for missed weights and reduces that priority after correct bit decisions. Later generated questions periodically include the current weak bit. This does not claim to be a validated assessment or personalized curriculum; it is a transparent practice heuristic whose purpose can be inspected directly in the feedback.

Local progress and accessible controls

Progress stores only a version number, aggregate session and answer counts, the best short-session score, small per-bit review counters, and the last selected setup. It does not store names, emails, raw answer history, or sensitive information. Private browsing, blocked storage, or quota errors are handled without preventing play. The Privacy Policy describes the optional analytics consent framework and how to remove a saved choice.

Each finger has an accessible name containing its weight and raised or lowered state. Focus indicators remain visible, controls do not depend on hover, motion-reduction preferences are respected, and the game avoids camera, microphone, geolocation, and payment permissions. The full instructions list controls, while the Contact page provides a public route for accessibility corrections.

Original clean-room educational game

BitReach was built from the mathematical facts of binary place value and an independently written product specification. It does not copy the discovered Windows tool's name, program, camera system, art, writing, tutorial sequence, or challenge design. The generated questions, code-drawn interactive hands, feedback language, local-progress model, visual identity, and production illustration are original to this project. The About page records this boundary and the project notices identify the runtime libraries used.

The site is a practice game, not a grade, certification, medical tool, or replacement for an instructor. If a displayed rule or place value is wrong, visitors can report the exact page and expected correction through the public support route. Terms explain availability and responsible use.