- IFS
- IFERROR
- IFNA
- IFS
- IMABS
- IMAGINARY
- IMARGUMENT
- IMCONJUGATE
- IMCOS
- IMCOSH
- IMCOT
- IMCSC
- IMCSCH
- IMDIV
- IMEXP
- IMLN
- IMLOG10
- IMLOG2
- IMPOWER
- IMPRODUCT
- IMREAL
- IMSEC
- IMSECH
- IMSIN
- IMSINH
- IMSQRT
- IMSUB
- IMSUM
- IMTAN
- INDEX
- INDIRECT
- INFO
- INT
- INTERCEPT
- INTRATE
- IPMT
- IRR
- ISBLANK
- ISERR
- ISERROR
- ISEVEN
- ISFORMULA
- ISLOGICAL
- ISNA
- ISNONTEXT
- ISNUMBER
- ISODD
- ISOWEEKNUM
- ISPMT
- ISREF
- ISTEXT