diff --git a/NAMESPACE b/NAMESPACE
index 3e6deff24..1c99b6d29 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -182,16 +182,19 @@ importFrom(grDevices,tiff)
 importFrom(magrittr,"%>%")
 importFrom(stringi,stri_c)
 importFrom(stringi,stri_encode)
+importFrom(stringi,stri_extract_all_regex)
 importFrom(stringi,stri_isempty)
 importFrom(stringi,stri_join)
 importFrom(stringi,stri_match)
 importFrom(stringi,stri_match_all_regex)
+importFrom(stringi,stri_match_first_regex)
 importFrom(stringi,stri_opts_collator)
 importFrom(stringi,stri_order)
 importFrom(stringi,stri_pad_left)
 importFrom(stringi,stri_rand_strings)
 importFrom(stringi,stri_read_lines)
 importFrom(stringi,stri_replace_all_fixed)
+importFrom(stringi,stri_replace_all_regex)
 importFrom(stringi,stri_split_fixed)
 importFrom(stringi,stri_split_regex)
 importFrom(stringi,stri_sub)
diff --git a/R/openxlsx2-package.R b/R/openxlsx2-package.R
index 6efe91cf0..4c4ca7389 100644
--- a/R/openxlsx2-package.R
+++ b/R/openxlsx2-package.R
@@ -12,11 +12,11 @@
 #' @import R6
 #' @importFrom grDevices bmp col2rgb colors dev.copy dev.list dev.off jpeg palette png rgb tiff
 #' @importFrom magrittr %>%
-#' @importFrom stringi stri_c stri_encode stri_isempty stri_join stri_match
-#'   stri_match_all_regex stri_order stri_opts_collator stri_pad_left
-#'   stri_rand_strings stri_read_lines stri_replace_all_fixed
-#'   stri_split_fixed stri_split_regex stri_sub stri_unescape_unicode
-#'   stri_unique
+#' @importFrom stringi stri_c stri_encode stri_extract_all_regex
+#'   stri_isempty stri_join stri_match stri_match_all_regex stri_match_first_regex
+#'   stri_order stri_opts_collator stri_pad_left stri_rand_strings stri_read_lines
+#'   stri_replace_all_fixed stri_replace_all_regex stri_split_fixed
+#'   stri_split_regex stri_sub stri_unescape_unicode stri_unique
 #' @importFrom utils download.file head menu read.csv unzip
 #' @importFrom zip zip
 #'
diff --git a/R/read.R b/R/read.R
index 13d38e0ea..73679ffa6 100644
--- a/R/read.R
+++ b/R/read.R
@@ -427,54 +427,29 @@ wb_to_df <- function(
 
     if (any(cc$f_t == "shared")) {
 
+      # depending on the sheet, this might require updates to many cells
+      # TODO reduce this to cells, that are part of `cc`. Currently we
+      # might waste time, updating cells that are not visible to the user
       cc_shared <- wb$worksheets[[sheet]]$sheet_data$cc
       cc_shared <- cc_shared[cc_shared$f_t == "shared", ]
       cc_shared <- cc_shared[order(as.integer(cc_shared$f_si)), ]
 
-      # extend shared formula into all formula cells
-      carry_forward <- function(x) {
-        last_val <- NA
-        for (i in seq_along(x)) {
-          if (x[i] != "") {
-            last_val <- x[i]
-          } else {
-            x[i] <- last_val
-          }
-        }
-        return(x)
-      }
+      # carry forward the shared formula
+      cc_shared$f    <- ave2(cc_shared$f, cc_shared$f_si, carry_forward)
 
-      cc_shared$f <- ave(
-        cc_shared$f,
-        as.integer(cc_shared$f_si),
-        FUN = carry_forward
-      )
-
-      # calculate difference for each shared formula to the origin
-      calc_distance <- function(x) {
-        x - x[1]
-      }
+      # calculate differences from the formula cell, to the shared cells
+      cc_shared$cols <- ave2(col2int(cc_shared$c_r), cc_shared$f_si, calc_distance)
+      cc_shared$rows <- ave2(as.integer(cc_shared$row_r), cc_shared$f_si, calc_distance)
 
-      cc_shared$cols <- ave(
-        col2int(cc_shared$c_r),
-        as.integer(cc_shared$f_si),
-        FUN = calc_distance
-      )
-      cc_shared$rows <- ave(
-        as.integer(cc_shared$row_r),
-        as.integer(cc_shared$f_si),
-        FUN = calc_distance
-      )
-
-      # TODO skip non A1 shared cells
+      # begin updating the formulas. find a1 notion, get the next cell, update formula
       cells <- find_a1_notation(cc_shared$f)
-      repls <- cells
+      repls <- vector("list", length = length(cells))
 
-      for (i in seq_len(nrow(cells))) {
-        repls[i, ] <- next_cell(cells[i, ], cc_shared$cols[i], cc_shared$rows[i])
+      for (i in seq_along(cells)) {
+        repls[[i]] <- next_cell(cells[[i]], cc_shared$cols[i], cc_shared$rows[i])
       }
 
-      cc_shared$f    <- replace_a1_notation(cc_shared["f"], cells, repls)
+      cc_shared$f    <- replace_a1_notation(cc_shared$f, repls)
       cc_shared$cols <- NULL
       cc_shared$rows <- NULL
 
diff --git a/R/utils.R b/R/utils.R
index 1e11cc871..5741815fe 100644
--- a/R/utils.R
+++ b/R/utils.R
@@ -1276,26 +1276,30 @@ get_dims <- function(dims, check = FALSE, cols = FALSE, rows = FALSE) {
 }
 
 #' the function to find the cell
+#' this function is used with `show_formula` in [wb_to_df()]
 #' @param string the formula
 #' @family internal
 #' @noRd
 find_a1_notation <- function(string) {
   pattern <- "\\$?[A-Z]\\$?[0-9]+(:\\$?[A-Z]\\$?[0-9]+)?"
-  as.data.frame(do.call("rbind", stringi::stri_extract_all_regex(string, pattern)))
+  stringi::stri_extract_all_regex(string, pattern)
 }
 
 #' the function to replace the next cell
+#' this function is used with `show_formula` in [wb_to_df()]
 #' @param cell the cell from a shared formula [find_a1_notation()]
 #' @param cols,rows an integer where to move the cell
 #' @family internal
 #' @noRd
 next_cell <- function(cell, cols = 0L, rows = 0L) {
-  z <- NULL
-  for (i in cell) {
+
+  z <- vector("character", length(cell))
+  for (i in seq_along(cell)) {
     # Match individual cells and ranges
-    match <- stringi::stri_match_first_regex(i, "^(\\$?)([A-Z]+)(\\$?)(\\d+)(:(\\$?)([A-Z]+)(\\$?)(\\d+))?$")
+    match <- stringi::stri_match_first_regex(cell[[i]], "^(\\$?)([A-Z]+)(\\$?)(\\d+)(:(\\$?)([A-Z]+)(\\$?)(\\d+))?$")
 
-    if (is.na(match[1, 1])) stop("Invalid A1 notation")
+    # if shared formula contains no A1 reference
+    if (is.na(match[1, 1])) return(NA_character_)
 
     # Extract parts of the cell
     fixed_col1 <- match[2]
@@ -1313,7 +1317,7 @@ next_cell <- function(cell, cols = 0L, rows = 0L) {
       # Handle individual cell
       next_col <- if (fixed_col1 == "") int2col(col2int(col1) + cols) else col1
       next_row <- if (fixed_row1 == "") row1 + rows else row1
-      z <- c(z, paste0(fixed_col1, next_col, fixed_row1, next_row))
+      z[i] <- paste0(fixed_col1, next_col, fixed_row1, next_row)
 
     } else {
 
@@ -1322,39 +1326,58 @@ next_cell <- function(cell, cols = 0L, rows = 0L) {
       next_row1 <- if (fixed_row1 == "") row1 + rows else row1
       next_col2 <- if (fixed_col2 == "") int2col(col2int(col2) + cols) else col2
       next_row2 <- if (fixed_col2 == "") row2 + rows else row2
-      z <- c(z, paste0(fixed_col1, next_col1, fixed_row1, next_row1, ":", fixed_col2, next_col2, fixed_row2, next_row2))
+      z[i] <- paste0(fixed_col1, next_col1, fixed_row1, next_row1, ":", fixed_col2, next_col2, fixed_row2, next_row2)
 
     }
   }
 
-  as.data.frame(matrix(z, ncol = 2))
+  z
 }
 
 #' the replacement function for shared formulas
+#' this function is used with `show_formula` in [wb_to_df()]
 #' @param string the formula
-#' @param matches the matches, obtained via [find_a1_notation()]
 #' @param replacements the replacements, from [next_cell()]
 #' @family internal
 #' @noRd
-replace_a1_notation <- function(strings, matches, replacements) {
-
-  # strings <- data.frame(rep(string, NROW(replacements)))
+replace_a1_notation <- function(strings, replacements) {
 
-  # matches <- as.data.frame(
-  #   matrix(matches, nrow = NROW(replacements), ncol = length(matches), byrow = TRUE)
-  # )
+  # create sprintf-able strings
+  strings <- stringi::stri_replace_all_regex(
+    strings,
+    "\\$?[A-Z]\\$?[0-9]+(:\\$?[A-Z]\\$?[0-9]+)?",
+    "%s"
+  )
 
-  repl_fun <- function(str, x, y) {
-    for (i in seq_along(x)) {
-      str <- stringi::stri_replace_first_fixed(str, x[i], y[i])
-    }
+  # insert replacements into string
+  repl_fun <- function(str, y) {
+    if (!anyNA(y)) # else keep str as is
+      str <- do.call(sprintf, c(str, as.list(y)))
     str
   }
 
-  z <- NULL
-  for (i in seq_len(NROW(strings))) {
-    z <- c(z, repl_fun(strings[i, ], matches[i, ], replacements[i, ]))
+  z <- vector("character", length(strings))
+  for (i in seq_along(strings)) {
+    z[i] <- repl_fun(strings[[i]], replacements[[i]])
   }
 
   z
 }
+
+# extend shared formula into all formula cells
+carry_forward <- function(x) {
+  rep(x[1], length(x))
+}
+
+# calculate difference for each shared formula to the origin
+calc_distance <- function(x) {
+  x - x[1]
+}
+
+# ave function to avoid a dependency on stats. if we ever rely on stats,
+# this can be replaced by stats::ave
+ave2 <- function (x, y, FUN) {
+  g <- as.factor(y)
+  split(x, g) <- lapply(split(x, g), FUN)
+  x
+}
diff --git a/tests/testthat/test-read_from_created_wb.R b/tests/testthat/test-read_from_created_wb.R
index 2e17a68d3..4c778b34f 100644
--- a/tests/testthat/test-read_from_created_wb.R
+++ b/tests/testthat/test-read_from_created_wb.R
@@ -223,9 +223,10 @@ test_that("check_names works", {
 })
 
 test_that("shared formulas are handled", {
+
   wb <- wb_workbook()$
     add_worksheet()$
-    add_data(x = matrix(rnorm(5*5), ncol = 5, nrow = 5))$
+    add_data(x = matrix(rnorm(5 * 5), ncol = 5, nrow = 5))$
     add_formula(x = "SUM($A2:A2) + B$1", dims = "A8:E12", shared = TRUE)
 
   exp <- structure(
@@ -237,4 +238,40 @@ test_that("shared formulas are handled", {
   )
   got <- as.matrix(wb_to_df(wb, dims = "A10:C12", col_names = FALSE, show_formula = TRUE))
   expect_equal(exp, got)
+
+  # shared formula w/o A1 notation
+  wb <- wb_workbook()$
+    add_worksheet()$
+    add_data(x = matrix(rnorm(5 * 5), ncol = 5, nrow = 5))$
+    add_formula(x = "TODAY()", dims = "A8:E12", shared = TRUE)
+
+  exp <- rep("TODAY()", 9)
+  got <- unname(unlist(wb_to_df(wb, dims = "A10:C12", col_names = FALSE, show_formula = TRUE)))
+  expect_equal(exp, got)
+
+  # a bunch of mixed shared formulas
+  wb <- wb_workbook()$
+    add_worksheet()$
+    add_data(x = matrix(rnorm(5 * 5), ncol = 5, nrow = 5))$
+    add_formula(x = "SUM($A2:A2) + B$1", dims = "A8:E9", shared = TRUE)$
+    add_formula(x = "SUM($A2:A2)", dims = "A10:E11", shared = TRUE)$
+    add_formula(x = "A2", dims = "A12:E13", shared = TRUE)
+
+  exp <- c("SUM($A2:B2) + C$1", "SUM($A3:B3) + C$1", "SUM($A2:B2)", "SUM($A3:B3)",
+           "B2", "B3", "SUM($A2:C2) + D$1", "SUM($A3:C3) + D$1", "SUM($A2:C2)",
+           "SUM($A3:C3)", "C2", "C3", "SUM($A2:D2) + E$1", "SUM($A3:D3) + E$1",
+           "SUM($A2:D2)", "SUM($A3:D3)", "D2", "D3")
+  got <- unname(unlist(wb_to_df(wb, dims = "B8:D13", col_names = FALSE, show_formula = TRUE)))
+  expect_equal(exp, got)
+
+  # make sure that replacements work as expected
+  wb <- wb_workbook()$
+    add_worksheet()$
+    add_data(x = matrix(rnorm(5 * 5), ncol = 5, nrow = 5))$
+    add_formula(x = "A2 + B2", dims = "A12:E13", shared = TRUE)
+
+  exp <- c("A2 + B2", "A3 + B3", "B2 + C2", "B3 + C3", "C2 + D2", "C3 + D3", "D2 + E2", "D3 + E3")
+  got <- unname(unlist(wb_to_df(wb, dims = "A12:D13", col_names = FALSE, show_formula = TRUE)))
+  expect_equal(exp, got)
+
 })