WEIBULL.DIST in ONLYOFFICE Spreadsheet Editor

• Introduced: Original introduction release is not established by the checked sources.
• Available: Listed in current unversioned ONLYOFFICE help, checked October 18, 2026.
• Implementation inspected: Official SDKJS v10.0.0.169, commit 3679e0375a758d7dc59d31337a45461be3525ed8. The snapshot does not prove identical behavior in every installed editor.
• Retired or deprecated: These sources do not establish retirement or formal deprecation.
• Testing: Numerical examples are independent mathematical expectations, and implementation discrepancies are labeled source predictions. No ONLYOFFICE application or calculation-engine execution was performed.

The examples use English function names and commas. Use your locale’s argument separator if different. Retain full precision in formulas; round only the displayed result. These examples establish only the stated mathematical or source-trace cases. Application rendering, array placement and general import/export behavior have not been tested.

=WEIBULL.DIST(x, alpha, beta, cumulative)
=WEIBULL(x, alpha, beta, cumulative)

Exactly four arguments are required. x is nonnegative, alpha is a positive shape, beta is a positive scale, and cumulative selects TRUE for the lower-tail CDF or FALSE for the probability density. The dotted function inherits the WEIBULL calculation in this inspected source snapshot, so the legacy name shares that calculation path.

The CDF is 1-EXP(-POWER(x/beta,alpha)). For positive x, the density is (alpha/beta)*(x/beta)^(alpha-1)*EXP(-POWER(x/beta,alpha)). Beta has the same units as x; alpha is dimensionless. Beta is not a rate and is not generally the mean.

At x=beta, the CDF is always 1−exp(−1), approximately 0.632120558829. With alpha=1, the distribution reduces to an exponential model with rate 1/beta. Other shapes change the distribution’s form; the formula does not estimate or validate the shape from your observations.

1. Put x 3 in A2, shape 2 in B2 and scale 3 in C2.
2. Enter =WEIBULL.DIST(A2,B2,C2,TRUE) in D2.
3. Enter =WEIBULL.DIST(A2,B2,C2,FALSE) in E2.
4. Independent expectations are 0.632120558829 and 0.245252960781 respectively.

Here x/beta=1. The CDF becomes 1−e⁻¹. The density becomes (2/3)e⁻¹. If x is measured in hours, the density is per hour, while the CDF is a unitless probability.

A density height is not the chance of an exact continuous value. The mathematical probability of exactly x=3 is zero; meaningful nonzero probabilities describe intervals. A density may exceed 1 when the measurement scale is sufficiently narrow without violating probability rules.

For shape 2 and scale 3, the probability of x between 3 and 6 is =WEIBULL.DIST(6,2,3,TRUE)-WEIBULL.DIST(3,2,3,TRUE). Independently this is EXP(-1)-EXP(-4), approximately 0.349563802283.

The survival probability above 6 is directly =EXP(-POWER(6/3,2)), approximately 0.018315638889. For very small tails, evaluating survival directly can avoid cancellation from subtracting a CDF extremely close to 1.

A median can be derived by setting the CDF to 0.5: x = beta×LN(2)^(1/alpha). For alpha=2 and beta=3, this is 2.497663833473. This is an independent algebraic calculation, not a claim that WEIBULL.DIST itself is an inverse function.

If hours are converted to minutes, multiply both x and beta by 60 while leaving alpha fixed. =WEIBULL.DIST(180,2,180,TRUE) represents the same event as the main CDF example. The density per minute is the density per hour divided by 60. Changing only x changes the model question rather than merely its display units.

The inspected wrapper rejects x<0, alpha<=0 or beta<=0 with internal not_numeric, conventionally #NUM!. Zero x itself is accepted. At x=0, the CDF is mathematically 0 for positive shape. Density behavior depends on shape:

• Alpha=1 gives 1/beta; with beta=2, the expectation is 0.5.
• Alpha>1 gives zero density; for alpha=2 and beta=3, the expectation is 0.
• For 0<alpha<1 the mathematical density is singular at zero. The inspected expression generates a nonfinite value, and the number constructor maps nonfinite results to #NUM!. This is a source prediction, not a captured application display.

Use genuine Boolean cumulative values. The implementation converts the flag numerically and takes the density branch only when it equals zero; other numeric values select the CDF. That coercion rule is not a reason to use undocumented non-Boolean flags in a portable workbook.

Existing conversion errors propagate. Very large ratios or exponents can overflow intermediate powers, and very small tails may underflow or lose precision through subtraction. The moderate examples do not establish numerical accuracy over every admissible parameter combination.

These calculations describe a selected continuous distribution. They do not fit data, handle censoring, establish independence or prove that observed times follow a Weibull model. Keep parameter estimates and their assumptions separate from the CDF/PDF calculation.

The inherited calculation supports treating WEIBULL and WEIBULL.DIST together for this snapshot. It does not establish every array, text-coercion, file-format or application-version behavior as identical. Recheck important boundary and interval examples when moving a workbook.

Recalculate representative formulas when moving a workbook between editors. Matching names do not guarantee identical argument coercion, array behavior, numerical precision or error handling. These source-derived examples do not establish automatic spill behavior or a general import/export guarantee.

• EXP
• LN
• POWER

• ONLYOFFICE WEIBULL.DIST help, checked October 18, 2026.
• Official SDKJS implementation, 13136–13194, tag v10.0.0.169 and exact commit above.
• ONLYOFFICE WEIBULL help, checked October 18, 2026.