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Excel

Excel Errors: #N/A, #VALUE!, #REF! and How to Fix

Excel errors explained: what #N/A, #VALUE!, #REF!, #NAME? and #DIV/0! mean, how to fix them, IFERROR vs IFNA…

September 27, 2026 12 min read
Excel

Excel Dynamic Arrays: FILTER, SORT, UNIQUE, LET

Excel dynamic arrays explained: FILTER, SORT, UNIQUE, SEQUENCE and LET, how spilling works, AND and OR in FILTER,…

September 27, 2026 13 min read
Excel

Excel VLOOKUP, XLOOKUP and INDEX MATCH Explained

Excel lookup functions explained: VLOOKUP, INDEX MATCH and XLOOKUP, exact vs approximate match, several criteria and why lookups…

September 27, 2026 14 min read
Excel

Excel SUMIFS, COUNTIFS and AVERAGEIFS Explained

Excel SUMIFS, COUNTIFS and AVERAGEIFS explained with one sales table: criteria, dates, wildcards, OR conditions and the traps,…

September 27, 2026 9 min read
Excel

Excel ROUND, MOD, RANK and AVERAGE Functions

Excel math and statistics functions explained: order of calculation, ROUND, MOD, AVERAGE, MEDIAN, RANK, STDEV and SUBTOTAL, with…

September 27, 2026 13 min read
Excel

Excel Dates and Times: DATEDIF, EDATE, WORKDAY

Excel dates and times explained: serial numbers, DATE, DATEDIF, EDATE, EOMONTH, WORKDAY and NETWORKDAYS, week numbers and time…

September 27, 2026 13 min read
Excel

Excel Text Functions: LEFT, MID, TEXTJOIN, TRIM

Excel text functions explained: LEFT, MID, RIGHT, FIND, SUBSTITUTE, TRIM and TEXTJOIN, how to split a name or…

September 27, 2026 12 min read
Excel

Excel IF, AND, OR and IFS Functions Explained

Excel logical functions explained: IF, nested IF, AND, OR, IFS and SWITCH, how to combine AND with OR,…

September 27, 2026 12 min read
Excel

Excel Data Types and Number Formats Explained

Excel data types and number formats explained: numbers, text, dates, numbers stored as text, custom formats and the…

September 27, 2026 13 min read
Excel

Excel Cell References: Relative, Absolute, Mixed

Excel cell references explained: relative, absolute ($A$1) and mixed ($A1, A$1) references, the F4 key, ranges, other sheets…

September 27, 2026 15 min read
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