ACOTH
Quirk foundCategory: Math and trigonometry · Last tested 2026-09-01
Real compatibility results for the ACOTH function: executed in Excel for the web, Google Sheets and LibreOffice Calc, with desktop Excel behavior from Microsoft’s official documentation (we do not run desktop Excel — Excel for the web is a different application and is executed separately). Syntax and links to that documentation are below.
Support matrix
| Engine | Documented | Live-tested | Verdict |
|---|---|---|---|
| Excel (desktop) | Yes | No — documented only | n/a |
| Excel for the web | — | Yes (recalc, 2026-09-01) | Supported, behaves as documented |
| Google Sheets | Yes | Yes (Drive import, 2026-08-31) | Supported, behaves as documented |
| LibreOffice Calc | Yes | Yes (25.8.7.3, 2026-08-31) | Quirk found |
LibreOffice version history
We executed the same test cases under each LibreOffice release to show exactly when ACOTH’s support changed — not documentation claims, real results.
| LibreOffice version | Verdict | Tested |
|---|---|---|
| 24.2.0.3 | Quirk found | 2026-08-31 |
| 24.8.7.2 | Quirk found | 2026-08-31 |
| 25.2.0.3 | Quirk found | 2026-08-31 |
| 25.8.7.3 | Quirk found | 2026-08-31 |
Why isn't ACOTH working in LibreOffice?
ACOTH exists in LibreOffice 25.8.7.3, but it is not a drop-in match for
Excel — our executed tests found real behavioral differences (detailed in the test results on this
page). If a formula that works in Excel or Google Sheets misbehaves in LibreOffice, compare your usage
against the failing cases above before assuming your data is wrong.
Discovered quirks
-
=ACOTH(0.5) on
LibreOffice Calc returned
#VALUE!, but the documented/expected
result is #NUM!.
Provenance
Excel documents: "If Number is less than 1, ACOTH returns the #NUM! error value." (The page's next line repeats the rule for the absolute value but misnames the function as ACOT and misnames the error as #VALUE!; the #NUM! statement is the one that names ACOTH, and 0.5 satisfies both stated conditions); MISMATCH vs expected: expected '#NUM!', got '#VALUE!'
Executed test cases
Excel for the web (executed 2026-09-01 via OneDrive recalculation)
These values come from Excel for the web, not from desktop Excel. They are two different implementations of the calculation engine, and this run measured only the web one: the corpus was uploaded to OneDrive as .xlsx, recalculated by Excel for the web on open, and downloaded again for readback. Excel for the web is a rolling service with no pinnable version, so the run is identified by its date. Where a value here disagrees with the Expected column — which is Microsoft’s documentation of the desktop product — we cannot tell you whether the web engine diverges from the desktop one or the documentation is wrong about both, because we do not run desktop Excel.
| Formula | Description | Result | Expected | Verdict |
|---|---|---|---|---|
| =ROUND(ACOTH(6),3) | Microsoft's documented worked example: inverse hyperbolic cotangent of 6 | 0.168 | 0.168ProvenanceMicrosoft's page publishes this example's result as 0.168. Independently verified from the documented identity acoth(x) = 0.5*ln((x+1)/(x-1)) = atanh(1/x): atanh(1/6) = 0.16823611831060645 -> 0.168 at 3 dp |
Matched |
| =ROUND(ACOTH(-2),9) | A negative argument whose absolute value exceeds 1, which the documented domain allows | -0.549306144 | -0.549306144ProvenanceExcel documents "The absolute value of Number must be greater than 1", so -2 is in the domain. Independently derived from 0.5*ln((x+1)/(x-1)) with x = -2: 0.5*ln(1/3) = -0.5493061443340548 -> -0.549306144 at 9 dp |
Matched |
| =ACOTH(0.5) | An argument whose absolute value is below 1 is outside the documented domain | #NUM! | #NUM!ProvenanceExcel documents: "If Number is less than 1, ACOTH returns the #NUM! error value." (The page's next line repeats the rule for the absolute value but misnames the function as ACOT and misnames the error as #VALUE!; the #NUM! statement is the one that names ACOTH, and 0.5 satisfies both stated conditions) |
Matched |
| =ACOTH("abc") | A non-numeric text argument | #VALUE! | #VALUE!Provenance#VALUE! is Excel's documented error for an argument of the wrong type; the companion ACOT page states it explicitly for this function family |
Matched |
Google Sheets (executed 2026-08-31 via Drive import)
Google Sheets is a rolling service with no pinnable version, so this run is identified by its date. The corpus was imported to Drive as .xlsx, recalculated by Sheets, and exported back for readback.
| Formula | Description | Result | Expected | Verdict |
|---|---|---|---|---|
| =ROUND(ACOTH(6),3) | Microsoft's documented worked example: inverse hyperbolic cotangent of 6 | 0.168 | 0.168ProvenanceMicrosoft's page publishes this example's result as 0.168. Independently verified from the documented identity acoth(x) = 0.5*ln((x+1)/(x-1)) = atanh(1/x): atanh(1/6) = 0.16823611831060645 -> 0.168 at 3 dp |
Matched |
| =ROUND(ACOTH(-2),9) | A negative argument whose absolute value exceeds 1, which the documented domain allows | -0.549306144 | -0.549306144ProvenanceExcel documents "The absolute value of Number must be greater than 1", so -2 is in the domain. Independently derived from 0.5*ln((x+1)/(x-1)) with x = -2: 0.5*ln(1/3) = -0.5493061443340548 -> -0.549306144 at 9 dp |
Matched |
| =ACOTH(0.5) | An argument whose absolute value is below 1 is outside the documented domain | #NUM! | #NUM!ProvenanceExcel documents: "If Number is less than 1, ACOTH returns the #NUM! error value." (The page's next line repeats the rule for the absolute value but misnames the function as ACOT and misnames the error as #VALUE!; the #NUM! statement is the one that names ACOTH, and 0.5 satisfies both stated conditions) |
Matched |
| =ACOTH("abc") | A non-numeric text argument | #VALUE! | #VALUE!Provenance#VALUE! is Excel's documented error for an argument of the wrong type; the companion ACOT page states it explicitly for this function family |
Matched |
LibreOffice Calc 25.8.7.3 (tested 2026-08-31)
| Formula | Description | Result | Expected | Verdict |
|---|---|---|---|---|
| =ROUND(ACOTH(6),3) | Microsoft's documented worked example: inverse hyperbolic cotangent of 6 | 0.168 | 0.168ProvenanceMicrosoft's page publishes this example's result as 0.168. Independently verified from the documented identity acoth(x) = 0.5*ln((x+1)/(x-1)) = atanh(1/x): atanh(1/6) = 0.16823611831060645 -> 0.168 at 3 dp |
Matched |
| =ROUND(ACOTH(-2),9) | A negative argument whose absolute value exceeds 1, which the documented domain allows | -0.549306144 | -0.549306144ProvenanceExcel documents "The absolute value of Number must be greater than 1", so -2 is in the domain. Independently derived from 0.5*ln((x+1)/(x-1)) with x = -2: 0.5*ln(1/3) = -0.5493061443340548 -> -0.549306144 at 9 dp |
Matched |
| =ACOTH(0.5) | An argument whose absolute value is below 1 is outside the documented domain | #VALUE! | #NUM!ProvenanceExcel documents: "If Number is less than 1, ACOTH returns the #NUM! error value." (The page's next line repeats the rule for the absolute value but misnames the function as ACOT and misnames the error as #VALUE!; the #NUM! statement is the one that names ACOTH, and 0.5 satisfies both stated conditions) |
Mismatch |
| =ACOTH("abc") | A non-numeric text argument | #VALUE! | #VALUE!Provenance#VALUE! is Excel's documented error for an argument of the wrong type; the companion ACOT page states it explicitly for this function family |
Matched |
Docs & syntax
- Excel (desktop): official documentation
- Google Sheets: official documentation
- LibreOffice Calc: official documentation