Frequently asked questions.

Precision periodization engine. Calyber logs your sets, detects RIR drift, and recalibrates the next session’s prescription. Every weight and rep target shows the basis it was computed from.

Same scientific methodology: MEV/MAV/MRV volume landmarks, RIR-based progression, autoregulation. Lower price during the Founding window ($19/mo locked vs $35/mo). Algorithm decisions are transparent and auditable, not coached.

Those apps log workouts. Calyber prescribes them and adapts based on what you logged. Periodization plus autoregulation, not just history.

MGFI is the Muscle Group Fatigue Index, a composite of soreness, pump, workload, and performance signals. RI is the Readiness Index (short-window readiness). AI is the Accumulation Index (decayed multi-session burden). Together they tell the algorithm when to push and when to deload.

No. The engine builds a baseline from your first session and refines it across the mesocycle using Epley-derived e1RM. Estimates improve as you log more data.

Yes. The autoregulation runs on your inputs (RIR, soreness, performance), not on your demographics. 84 templates cover Upper/Lower, Push/Pull/Legs, Whole-Body, and 8 split categories.

Not at launch. Import from other logging apps is on the post-launch roadmap.

Your data is retained in read-only form. You can export logs as CSV or JSON (post-launch). Re-subscribing restores write access; Founding pricing does not return after a lapse (see the refund policy).

Calyber is a Progressive Web App. Install it from your browser to your home screen on iOS or Android. The full feature set is available on mobile.

The algorithm is deterministic and auditable. Every prescription shows the math it was computed from. "AI-powered" implies a black box; Calyber is the opposite.

Most percentage-based programs assume your 1RM is fixed and accurate. Calyber treats e1RM as a moving estimate and uses RIR-based daily autoregulation, which research suggests outperforms fixed percentages for hypertrophy.

The 28-day free trial is the evaluation window. Once paid, refunds are issued for technical defects only: 7 days from first charge on monthly plans, 14 days on annual. Founding lock-in pricing is forfeited on any lapse. Full terms on the refund policy page.