LET

Quirk found

Category: Logical · Last tested 2026-08-29

Real compatibility results for the LET function: executed in 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.

✓ Supported in LibreOffice since 24.8.7.2. We ran LET under every LibreOffice release we test (24.2.0.3, 24.8.7.2, 25.2.0.3, 25.8.7.3): it returned #NAME? (unrecognized) in 24.2.0.3 and first works in 24.8.7.2. If you need LET in LibreOffice Calc, use 24.8.7.2 or newer.

Support matrix

Engine	Documented	Live-tested	Verdict
Excel (desktop)	Yes	No — documented only	n/a
Excel for the web	—	No — file could not be opened	n/a
Google Sheets	Yes	Yes (Drive import, 2026-08-29)	Quirk found
LibreOffice Calc	Yes	Yes (25.8.7.3, 2026-07-29)	Supported, behaves as documented

LibreOffice version history

We executed the same test cases under each LibreOffice release to show exactly when LET’s support changed — not documentation claims, real results.

LibreOffice version	Verdict	Tested
24.2.0.3	Unsupported (not recognized)	2026-08-29
24.8.7.2	Supported, behaves as documented	2026-08-29
25.2.0.3	Supported, behaves as documented	2026-08-29
25.8.7.3	Supported, behaves as documented	2026-07-29

Why isn't LET working in LibreOffice?

If LET returns a #NAME? error in LibreOffice Calc, you are almost certainly running a release older than 24.8.7.2 — that is exactly what our executed tests show: #NAME? in 24.2.0.3, working from 24.8.7.2 onward. Check your version under Help → About LibreOffice and upgrade to 24.8.7.2 or newer; no setting or extension enables it in older releases. (Other causes of this error: see the error values guide.)

Why isn’t LET working in Google Sheets?

LET runs in Google Sheets, but our executed cases show it does not match Excel’s documented behavior on every input (the failing cases are listed on this page). If a formula that behaves one way in Excel gives you a different answer in Sheets, compare your usage against those cases before assuming your data is wrong.

Excel for the web: not testable through our transport. Not reachable through this harness’s transport — not a statement about Excel. Excel for the web is reached by uploading an .xlsx to OneDrive and opening it, and its file-open refuses any workbook whose stored formulas carry the _xlpm./LAMBDA storage serialization (“Couldn’t Open the Workbook”, no cell-level diagnostic). Proven by bisect: the 40-function chunk carrying it was refused, the same chunk minus LAMBDA/LET/ISOMITTED opened, and those three alone were refused again. Desktop Excel implements LET — it is Microsoft’s own function — and LibreOffice’s executed verdict for it is published below. What we cannot do is carry it into the web engine to measure, so no Excel-for-the-web verdict is drawn. The irony is the finding: Excel for the web will not open a file containing Excel’s own LAMBDA-family storage serialization.

Discovered quirks

=LET(x,5,y,x*2) on Google Sheets returned #N/A, but the documented/expected result is #VALUE!.
Provenance
LET requires pairs plus a trailing calculation; here the last pair has no calc term following it in this deliberately malformed call; MISMATCH vs expected: expected '#VALUE!', got '#N/A'

Executed test cases

Google Sheets (executed 2026-08-29 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
=LET(x,5,x*2)	Single binding used in the calculation	10	10	Matched
=LET(a,2,b,a*3,a+b)	Later bindings can reference earlier ones in the same LET	8	8	Matched
=LET(rng,{1,2,3},SUM(rng))	LET can bind an array literal and pass it to another function	6	6	Matched
=LET(x,5,y,x*2)	Odd total arg count (missing final calculation expression) is a syntax/value error	#N/A	#VALUE! Provenance LET requires pairs plus a trailing calculation; here the last pair has no calc term following it in this deliberately malformed call	Mismatch

LibreOffice Calc 25.8.7.3 (tested 2026-07-29)

Formula	Description	Result	Expected	Verdict
=LET(x,5,x*2)	Single binding used in the calculation	10	10	Matched
=LET(a,2,b,a*3,a+b)	Later bindings can reference earlier ones in the same LET	8	8	Matched
=LET(rng,{1,2,3},SUM(rng))	LET can bind an array literal and pass it to another function	6	6	Matched
=LET(x,5,y,x*2)	Odd total arg count (missing final calculation expression) is a syntax/value error	#VALUE!	#VALUE! Provenance LET requires pairs plus a trailing calculation; here the last pair has no calc term following it in this deliberately malformed call	Matched

Docs & syntax

Excel (desktop): official documentation
Google Sheets: official documentation
LibreOffice Calc: official documentation

Where LET behaves differently

Which LibreOffice version for VSTACK, TEXTSPLIT, TAKE & DROP?
VSTACK, HSTACK, TEXTSPLIT, TAKE and DROP return #NAME? in LibreOffice 24.2, 24.8 and 25.2 - our executed runs show all fourteen working only from 25.8.7.3. Full version map by wave.