Stratum iconStratum

Minitab alternative · SPC included

A modern Minitab alternative — control charts included.

Stop renewing a subscription you have to ask the price of: Stratum is one-time, Professional at $249, and runs as natively on a Mac as on Windows — so everyone works in the same app. Capability intervals come from the exact noncentral t, not the normal approximation most packages settle for.

30+
Chart & analysis types
~5M
Rows, smoothly
Once
One payment, not annual
2
Platforms, equally native
A process capability report in Stratum showing Cp, Cpk, Cpm, Pp and Ppk with 95% confidence intervals beside a capability histogram with specification limits
Capability, with its uncertainty. Cp, Cpk, Cpm, Pp and Ppk reported with 95% confidence intervals beside the histogram and its specification limits — so a capability number arrives with how well it is pinned down.
An EWMA control chart of conductivity with control limits and out-of-control points flagged
Nine charts, one app. I-MR, X̄-R, X̄-S, p, np, c, u, CUSUM and EWMA — the whole set, not a subset of it.
An X-bar and R chart in Stratum split into a Phase I baseline and a Phase II monitoring stage: the baseline limits run flat across the divider and catch a drift at subgroups 37 to 39
Baseline, then monitoring. Limits estimated from the Phase I period and carried flat across everything after it — which is exactly what catches the drift at subgroups 37 to 39. Or re-estimate them per stage, your choice.
A p-chart in Stratum whose control limits step with each lot's inspected quantity, with one point flagged above the limit
Variable-width limits. Limits that step with each subgroup’s size — p, np, c and u, not just p and c — so a smaller subgroup is judged against its own, wider, limit.
A linear regression report in Stratum: the coefficients table with confidence intervals and VIF, and an Effect Tests table with GVIF, in the same report
Not only SPC. ANOVA, MANOVA and regression with the diagnostics in the same report — so the everyday work does not need a second package.

Minitab vs Stratum

A subscription doesn't end. A one-time purchase does.

Minitab

Minitab won’t quote a price without a sales call — its pricing page is a contact form. Whatever the number turns out to be, it returns every year, and access stops when you stop paying.

Yr 1Pay Yr 2Pay Yr 3Pay Yr 4Pay Yr 5Pay

Five years, five bills — and no software left if you stop.

Stratum

Bought once. The version you buy keeps working forever, online or off, on Mac and Windows alike.

Yr 2— Yr 3— Yr 4— Yr 5—

$249 for Professional — once, and it's yours.

 MinitabStratum
PricingAnnual subscription — price on requestOne-time (Professional $249)
PlatformWindows-firstNative to Mac & Windows
SPC control chartsYesI-MR, X̄-R, X̄-S, p, np, c, u, CUSUM, EWMA (Professional)
Out-of-control rulesYesAll eight Nelson rules, toggled per chart, with a Western Electric preset
Phases & stagesYesPhase I baseline carried forward, or limits re-estimated per stage
Given control limitsYesHistorical and standard values accepted in place of estimates
Process capabilityYesCp, Cpk, CPL, CPU, Cpm, Pp, Ppk, PPL, PPU, PPM and Z-bench (Professional)
Capability intervalsBissell normal approximationExact noncentral t — the form that approximation stands in for
Non-normal capabilityYesLognormal, Weibull, exponential — percentile indices to ISO 22514-2
Linked selectionBrushing on graphsOne row selection across the datasheet and every chart — select the out-of-control points and they light up everywhere
Everyday stats & chartsYes30+ charts, ANOVA and MANOVA, regression with diagnostics, contingency
Numerical validationMethods and formulas documentedPublished validation record — the outside tool named for every statistic, including the gaps
Where your Minitab analyses live in Stratum — menu path by menu path
Minitab · Stat ▸ Basic Statistics ▸ Display Descriptive Statistics

Summary — mean, SD, quartiles, skewness and kurtosis for every column at once, with counts and percentages.

Minitab · Stat ▸ Basic Statistics ▸ 2-Sample t

Two-Sample — Student's t, Welch and paired, with Mann-Whitney and Wilcoxon in the same report.

Minitab · Stat ▸ Basic Statistics ▸ Correlation

Correlation — Pearson, Spearman and Kendall matrices with confidence intervals and multiple-comparison correction.

Minitab · Stat ▸ ANOVA ▸ One-Way

One-Way ANOVA — SS, df, MS, F and p, with Tukey HSD post-hoc comparisons and Levene's test.

Minitab · Stat ▸ Regression ▸ Regression ▸ Fit Regression Model

Linear Regression — coefficients with CIs, VIF, leverage, Cook's D, best-subsets, R², AIC and BIC.

Minitab · Stat ▸ Tables ▸ Cross Tabulation and Chi-Square

Contingency Table — chi-square, expected counts, row / column percentages and a mosaic plot.

Minitab · Stat ▸ Multivariate ▸ Principal Components

Principal Components — loadings and variance explained, with a scree plot and biplot.

Minitab · Stat ▸ Multivariate ▸ Cluster K-Means

Clustering — K-means and hierarchical, with dendrograms.

Minitab · Stat ▸ Control Charts ▸ Variables Charts for Individuals ▸ I-MR

Control Charts — I-MR and X̄ with control limits and all eight Nelson rules.

Minitab · Stat ▸ Control Charts ▸ Attributes Charts ▸ P, C

Attribute Charts — p and c charts with variable-width limits for unequal subgroup sizes.

Minitab · Stat ▸ Control Charts ▸ Time-Weighted Charts ▸ CUSUM, EWMA

CUSUM & EWMA — tabular CUSUM with FIR head start, and EWMA with time-varying limit widths.

Minitab · Stat ▸ Quality Tools ▸ Capability Analysis ▸ Normal

Process Capability — Cp, Cpk, Pp, Ppk and PPM, with within and overall sigma reported side by side.

Minitab · Graph ▸ Histogram / Boxplot / Scatterplot

30+ chart types — histogram, box, violin, density, ECDF, Q-Q, scatter with OLS/LOESS, treemap, mosaic, Pareto and more.

Point-and-click throughout — and equally native on a Mac, where Minitab is Windows-first.

What you get for quality work

Stratum's Professional edition includes SPC control charts and full process-capability analysis (Cp, Cpk, Pp, Ppk, and PPM) alongside the everyday toolkit — descriptive statistics, ANOVA, correlation, contingency tests, and regression with diagnostics — plus data mining (decision trees, random forests, boosted trees, clustering) and multivariate methods (PCA, correspondence analysis, MANOVA). Import your .csv, .xlsx, fixed-width ASCII, SPSS .sav or Stata .dta and try it on your own process data first.

Frequently asked questions

Does Stratum do SPC control charts and process capability?

Yes — both are in the Professional edition. Nine control charts with all eight Nelson rules and Phase I/II staging, and capability reporting Cp, Cpk, CPL, CPU, Cpm, Pp, Ppk, PPL, PPU, PPM and Z-bench, each with a confidence interval, plus a capability histogram.

Will my capability numbers match the ones I have now?

The indices match. The confidence intervals can differ in the second decimal, because Stratum inverts the exact noncentral t where Minitab uses Bissell's normal approximation to it. The validation record documents the difference and the reference values behind it.

Is it a subscription?

No — Stratum is a one-time purchase. You can upgrade from Standard to Professional later.