Statistical Design Software

The Modern Standard for Experimental Design

Stop paying $1,000+ for clunky desktop software. Run Group Sequential designs, Adaptive Randomization, Basket, Umbrella, and Platform trials, SSR, CUPED, and Bayesian simulations for continuous, binary, and survival endpoints — directly in your browser.

629

Validation tests against gold standards

8

Real trial replications (NEJM, Lancet, JAMA)

$99

Per month vs $4,995/yr for nQuery

Figure 1

O'Brien-Fleming Stopping Boundaries

gsDesign v3.6
432100.00.250.50.751.0Information FractionZ-valueEfficacy (α=0.025)Futility (β=0.10)

Parameters

DesignO'Brien-Fleming
Interim Analyses4
Alpha (one-sided)0.025
Power90%
Max Sample Size2,847
Expected N (H1)1,923

Output matches gsDesign R package v3.6.0

Figure 2

Conditional Power Zone Classification

Mehta & Pocock 2011
FutilityUnfavorableKeep NPromisingIncrease NFavorableKeep N0.00.100.300.801.0Conditional PowerCP = 0.38Observed δ = 0.15CP = 0.85Planned δ = 0.30Observed interimPlanned design

Parameters

DesignUnblinded SSR
Planned Effect (δ)0.30
Observed Effect0.15
CP Thresholds0.10 / 0.30 / 0.80
Initial N468
Re-estimated N1,402

Zone classification per Mehta & Pocock (2011)

Figure 3

Blinded Sample Size Re-estimation

Zucker & Denne 2002
030060090012000.0×0.5×1.0×1.5×2.0×2.5×Observed / Planned VarianceTotal NCap (2.0×)PlannedN = 468N = 936Re-estimated NMax N cap

Parameters

DesignBlinded SSR
Effect Size (δ)0.30
Planned Variance1.0
Alpha (one-sided)0.025
Power90%
Initial N468
Cap (nmax)2.0× → 936

Variance-based re-estimation per Zucker & Denne (2002)

Why Zetyra

Clinical Rigor.
Regulatory Integrity.

Statistical engines built for the highest levels of scrutiny. Transparent, reproducible, and benchmarked against industry standards to support FDA- and EMA-ready trial design.

Standardized R-Backends

Eliminate “black box” calculations. Zetyra utilizes standardized R-backends for statistical legitimacy, providing full methodology transparency for your SAP.

High-Performance Simulation

Built for computational velocity. Run complex Monte Carlo simulations and adaptive design iterations at scale without legacy desktop latency.

Benchmarked Precision

Algorithms rigorously cross-validated against established standards, achieving numerical parity with industry-leading software.

Table 1

Validation Against Industry Standards

Industry StandardParity LevelGuideline Alignment
Two-sample t-test (Satterthwaite)Full ParityConsistent with ICH E9 principles
GSD (O'Brien-Fleming)Full ParityDesigned for FDA/EMA Stopping Rules
CUPED Variance ReductionFull ParityFDA Covariate Adjustment Guidance (2023)
Sample Size Re-estimation (Blinded & Unblinded)Full ParityFDA Adaptive Designs Guidance (2019)
Adaptive Randomization (RAR + Minimization)Full ParityFDA Adaptive Designs Guidance (2019)
Master Protocols (Basket, Umbrella, Platform)Full ParityFDA Master Protocols Guidance (2022)
Bayesian Toolkit (6 calculators)Full ParityFDA Draft Bayesian Guidance (2026)

Adaptive Design Integrity

Optimize trial efficiency with Group Sequential boundaries and Sample Size Re-estimation. Use O'Brien-Fleming or Pocock stopping rules, blinded variance re-estimation, or promising zone methods — all for continuous, binary, and survival endpoints. Zetyra ensures that the preservation of the family-wise error rate is mathematically sound and fully reproducible.

Calculators

Professional Suite

From basic power analysis to advanced adaptive designs.

View All Calculators

Frequentist

PRO

Survival, GSD (O'Brien-Fleming / Pocock), CUPED variance reduction

Adaptive

PRO

Blinded & unblinded sample size re-estimation, response-adaptive randomization (DBCD, Thompson, Neyman), Pocock-Simon minimization

Master Protocol

PRO

Basket (BHM, EXNEX), umbrella, platform (MAMS) — validated against I-SPY 2, STAMPEDE, REMAP-CAP

Bayesian ToolkitAdd-onFDA Aligned

End-to-end Bayesian workflow: define priors, borrow historical data, size trials, monitor interim analyses. Aligned with FDA January 2026 draft guidance.

Free

Free

Two-sample t-test, chi-square, basic power analysis — no signup required

Pricing

Simple Plans

Start free. Upgrade when you need advanced features. Cancel anytime.

Competitor pricing

nQuery Pro: $4,995/yr

Zetyra Pro: $99/mo

Free

The Essentials

$0/forever
  • Standard sample size calculator
  • Two-sample t-test
  • Chi-square calculator
  • No signup required
Use Now

Pro

Recommended

Evidence Pro

$99/mo

$29/mo for .edu

  • Continuous, binary & survival endpoints
  • GSD, Blinded SSR, Unblinded SSR
  • CUPED variance reduction
  • RAR, Basket, Umbrella & Platform trials
Start Free Trial

+ Bayesian Toolkit add-on from $49/mo

Team

Evidence Collective

$349/mo

5 seats included

  • Everything in Pro
  • Shared project library
  • Priority support
Start Team Trial

Enterprise

Custom

Contact
  • SSO / SAML
  • On-premise option
  • 21 CFR Part 11
Contact Sales

Testimonials

What Our Users Say

Trusted by biostatisticians and clinical researchers to support rigorous trial design.

Zetyra was a great tool for our team to reassure us about our planned interim analysis for our clinical trial. The calculator helped inform our decision-making for our safety monitoring process to support trial integrity.

Kylie M.|Principal Investigator

FAQ

Questions & Answers

Everything you need to know about Zetyra.

Have more questions?

Contact our team

We maintain an open-source validation suite with 629 automated tests across 33 scripts against industry gold standards. Our GSD module matches gsDesign within 0.04 z-score units. Adaptive and master protocol calculators are validated against Rosenberger theory, BHM/EXNEX conjugate posteriors, and three landmark trials (I-SPY 2, STAMPEDE, REMAP-CAP). We also replicate HPTN 083, HeartMate II, PACIFIC, and MONALEESA-7. View our full validation suite at github.com/evidenceinthewild/zetyra-validation.

All calculators use custom Python implementations built on NumPy and SciPy. GSD boundaries are validated against gsDesign (R) within 0.04 z-score units; SSR against Kieser-Friede and Mehta-Pocock; Bayesian methods against conjugate priors and Zhou & Ji (2024); adaptive randomization against Rosenberger optimal allocation theory; and master protocol designs against I-SPY 2, STAMPEDE, and REMAP-CAP published results.

Yes. Zetyra's calculations are validated against industry-standard references (gsDesign, rpact, published formulas) with 629 automated tests across 33 scripts. Our Bayesian Toolkit aligns with the FDA's January 2026 draft guidance on Bayesian methods. Master protocol calculators are validated against published trial results (I-SPY 2, STAMPEDE, REMAP-CAP). For regulatory submissions, we recommend including the exported PDF report alongside your Statistical Analysis Plan.

Yes. Pro users can export professional PDF reports that include all input parameters, methodology citations, and results. Reports are designed to be included directly in your Statistical Analysis Plan for regulatory submissions.

Yes. Evidence Pro and above includes REST API access for programmatic use of all calculators. See our API documentation at zetyra.com/docs/api. For custom integrations or bulk workflows, contact sales@zetyra.com.

No. All plans are month-to-month. Cancel anytime with no questions asked.

Zetyra provides equivalent statistical accuracy—validated against gsDesign, rpact, and published formulas with 629 automated tests—at a fraction of the cost. PASS/nQuery offer broader legacy test coverage but require expensive desktop licenses ($6,000-$15,000/year). Zetyra covers modern clinical trial designs (GSD, SSR, CUPED, Bayesian Toolkit, RAR, basket/umbrella/platform trials) across continuous, binary, and survival endpoints, runs in your browser with no installation, and enables easy sharing—starting at $99/mo.

We treat your designs as confidential. All data is encrypted in transit (TLS 1.3) and at rest. Input parameters are processed in real-time and not stored unless you explicitly save a project. We never use your data to train models or share it with third parties.

Evidence Collective ($349/month) includes 5 team seats, everything in Pro, a shared project library, team commenting and review features, and priority email support. It's designed for biostatistics departments that need to collaborate on trial designs. Additional seats can be added for $49/month each.

Yes! Academic users with a .edu email get Evidence Pro for just $29/month—70% off the standard price. This applies to graduate students, postdocs, and faculty. Sign up with your .edu email to automatically receive the discount.

If you cancel your Pro subscription, you retain access until the end of your billing period. Afterwards, your account reverts to the free tier. Your saved projects remain in your account as read-only (you can view and export them, but not edit).