diff --git a/docs/extras/trim.md b/docs/extras/trim.md
index 5789a0e97..fe9c6a806 100644
--- a/docs/extras/trim.md
+++ b/docs/extras/trim.md
@@ -24,14 +24,9 @@ This extra is composed of 1 small file:
 
 ## Methods
 
-The `trim` extra overrides one method and adds a utility helper to the `Pagy::Frontend` module. The overridden method is alias-chained with `*_with_trim` and `*_without_trim`)
+The `trim` extra overrides the `pagy_link_proc` method in the `Pagy::Frontend` module.
 
 ### pagy_link_proc(pagy, link_extra='')
 
-This extra overrides the `pagy_link_proc` method of the `Pagy::Frontend` module in order to trim the `:page_param` param from the first page link.
-
-### pagy_trim_url(url, param_string)
-
-This is the utility helper used internally in order to remove the `param_string` from the `url`. The `param_string` must be the complete string of name and value: e.g. `"page=1"`.
-
+This method trims the `:page_param` param from the first page link. It is alias-chained with `*_with_trim` and `*_without_trim`.
 
diff --git a/lib/pagy/extras/trim.rb b/lib/pagy/extras/trim.rb
index 0e321ed73..874b25502 100644
--- a/lib/pagy/extras/trim.rb
+++ b/lib/pagy/extras/trim.rb
@@ -8,23 +8,26 @@ module Frontend
     # boolean used by the compact navs
     TRIM = true
 
-    def pagy_trim_url(url, param_string)
-      url.sub(/((?:[?&])#{param_string}\z|\b(?<=[?&])#{param_string}&)/, '')
-    end
-
     alias_method :pagy_link_proc_without_trim, :pagy_link_proc
     def pagy_link_proc_with_trim(pagy, link_extra='')
       p_prev, p_next, p_vars = pagy.prev, pagy.next, pagy.vars
-      url   = pagy_url_for(MARKER, pagy)
-      p1url = pagy_trim_url(url, "#{p_vars[:page_param]}=#{MARKER}")
-      p1    = %(<a href="#{p1url}" #{p_vars[:link_extra]} #{link_extra})
-      a, b = %(<a href="#{url}" #{p_vars[:link_extra]} #{link_extra}).split(MARKER, 2)
-      -> (n, text=n, extra='') { start = n.to_i == 1 ? p1 : "#{a}#{n}#{b}"
+      marker_url = pagy_url_for(MARKER, pagy)
+      page1_url  = pagy_trim_url(marker_url, "#{p_vars[:page_param]}=#{MARKER}")
+      page1_link = %(<a href="#{page1_url}" #{p_vars[:link_extra]} #{link_extra})
+      a, b = %(<a href="#{marker_url}" #{p_vars[:link_extra]} #{link_extra}).split(MARKER, 2)
+      -> (n, text=n, extra='') { start = n.to_i == 1 ? page1_link : "#{a}#{n}#{b}"
                                  "#{start}#{ if    n == p_prev ; ' rel="prev"'
                                              elsif n == p_next ; ' rel="next"'
                                              else                           '' end } #{extra}>#{text}</a>" }
     end
     alias_method :pagy_link_proc, :pagy_link_proc_with_trim
 
+    private
+
+      # separate method easier to test
+      def pagy_trim_url(url, param_string)
+        url.sub(/((?:[?&])#{param_string}\z|\b(?<=[?&])#{param_string}&)/, '')
+      end
+
   end
 end
diff --git a/test/pagy/extras/trim_test.rb b/test/pagy/extras/trim_test.rb
index adb5b4b01..b8a3af4f2 100644
--- a/test/pagy/extras/trim_test.rb
+++ b/test/pagy/extras/trim_test.rb
@@ -16,10 +16,10 @@
   describe "#pagy_trim_url" do
 
     it 'trims urls' do
-      frontend.pagy_trim_url('foo/bar?page=1', 'page=1').must_equal('foo/bar')
-      frontend.pagy_trim_url('foo/bar?a=page&page=1', 'page=1').must_equal('foo/bar?a=page')
-      frontend.pagy_trim_url('foo/bar?a=page&page=1&b=4', 'page=1').must_equal('foo/bar?a=page&b=4')
-      frontend.pagy_trim_url('foo/bar?a=page&page=1&b=4&my_page=1', 'page=1').must_equal('foo/bar?a=page&b=4&my_page=1')
+      frontend.send(:pagy_trim_url, 'foo/bar?page=1', 'page=1').must_equal('foo/bar')
+      frontend.send(:pagy_trim_url, 'foo/bar?a=page&page=1', 'page=1').must_equal('foo/bar?a=page')
+      frontend.send(:pagy_trim_url, 'foo/bar?a=page&page=1&b=4', 'page=1').must_equal('foo/bar?a=page&b=4')
+      frontend.send(:pagy_trim_url, 'foo/bar?a=page&page=1&b=4&my_page=1', 'page=1').must_equal('foo/bar?a=page&b=4&my_page=1')
     end
 
   end