diff --git a/DESCRIPTION b/DESCRIPTION
index 1bddd9f4a..f2f818149 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -46,6 +46,7 @@ Suggests:
     dplyr (>= 1.1),
     effectsize,
     emmeans,
+    fixest,
     gamm4,
     ggplot2 (>= 3.5.0),
     gt,
diff --git a/NEWS.md b/NEWS.md
index efc2d873b..d597bbe15 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,9 @@
+# datawizard (development)
+
+CHANGES
+
+* `standardize()` now works on `fixest` estimations (#665).
+
 # datawizard 1.3.0
 
 BREAKING CHANGES
diff --git a/R/standardize.models.R b/R/standardize.models.R
index cd11d01ae..12a56d331 100644
--- a/R/standardize.models.R
+++ b/R/standardize.models.R
@@ -80,14 +80,6 @@ standardize.default <- function(
     return(x)
   }
 
-  # check model formula. Some notations don't work when standardizing data
-  insight::formula_ok(
-    x,
-    action = "error",
-    prefix_msg = "Model cannot be standardized.",
-    verbose = verbose
-  )
-
   data_std <- NULL # needed to avoid note
   .standardize_models(
     x,
@@ -112,6 +104,14 @@ standardize.default <- function(
   update_expr,
   ...
 ) {
+  # check model formula. Some notations don't work when standardizing data
+  insight::formula_ok(
+    x,
+    action = "error",
+    prefix_msg = "Model cannot be standardized.",
+    verbose = verbose
+  )
+
   m_info <- .get_model_info(x, ...)
   model_data <- insight::get_data(x, source = "mf", verbose = FALSE)
 
@@ -423,7 +423,8 @@ standardize.mediate <- function(
   #
   #   control.value <- temp_vals[1]
   #   treat.value <- temp_vals[2]
-  #   if (verbose) insight::format_alert("control and treatment values have been rescaled to their standardized scales.")
+  #   if (verbose) insight::format_alert("control and treatment values have been
+  #   rescaled to their standardized scales.")
   # }
 
   if (verbose && !all(c(control.value, treat.value) %in% c(0, 1))) {
@@ -471,8 +472,29 @@ standardize.biglm <- standardize.wbm
 # biglm doesn't regit the model to new data - it ADDs MORE data to the model.
 
 #' @export
-standardize.fixest <- standardize.wbm
-# fixest handles its own environment - so we can't update
+# Almost the same as `standardize.default()` but we pass `use_calling_env` in
+# update().
+standardize.fixest <- function(
+  x,
+  robust = FALSE,
+  two_sd = FALSE,
+  weights = TRUE,
+  verbose = TRUE,
+  include_response = TRUE,
+  ...
+) {
+  data_std <- NULL # needed to avoid note
+  .standardize_models(
+    x,
+    robust = robust,
+    two_sd = two_sd,
+    weights = weights,
+    verbose = verbose,
+    include_response = include_response,
+    update_expr = stats::update(x, data = data_std, use_calling_env = FALSE),
+    ...
+  )
+}
 
 # helper ----------------------------
 
diff --git a/tests/testthat/test-standardize_models.R b/tests/testthat/test-standardize_models.R
index e2043240e..1c41b03f0 100644
--- a/tests/testthat/test-standardize_models.R
+++ b/tests/testthat/test-standardize_models.R
@@ -401,3 +401,55 @@ test_that("brms", {
     regexp = "without adjusting priors may lead to bogus"
   )
 })
+
+# fixest --------------------------------------------------------------------
+
+test_that("fixest", {
+  skip_if_not_installed("fixest")
+
+  mtcars_stand <- standardize(mtcars)
+  orig <- fixest::feols(
+    drat ~ mpg + hp^2 | cyl + am,
+    data = mtcars,
+    se = "hetero"
+  )
+  # TODO: Remove this suppressWarnings() when a new version of `fixest` that
+  # contains the fix for https://github.com/lrberge/fixest/issues/618 is on CRAN
+  # (CRAN version is 0.13.2 at the time of writing).
+  suppressWarnings({
+    auto_stand <- standardize(orig)
+  })
+  manual_stand <- fixest::feols(
+    drat ~ mpg + hp^2 | cyl + am,
+    data = mtcars_stand,
+    se = "hetero"
+  )
+
+  # Need to unname because I(hp^2) in the manual one becomes I(I(hp ^2)) in the
+  # automated one.
+  expect_identical(
+    unname(auto_stand$coefficients),
+    unname(manual_stand$coefficients)
+  )
+  expect_identical(unname(auto_stand$se), unname(manual_stand$se))
+
+  ### Inform the user if some terms are log() or sqrt()
+  orig <- fixest::feols(
+    drat ~ log(mpg) | cyl + am,
+    data = mtcars
+  )
+  # TODO: same as above
+  expect_message(
+    suppressWarnings(standardize(orig)),
+    "Formula contains log- or sqrt-terms"
+  )
+  orig <- fixest::feols(
+    drat ~ sqrt(mpg) | cyl + am,
+    data = mtcars
+  )
+  # TODO: same as above
+  expect_message(
+    suppressWarnings(standardize(orig)),
+    "Formula contains log- or sqrt-terms"
+  )
+})