diff --git a/imgui-sys-bindgen/src/lib.rs b/imgui-sys-bindgen/src/lib.rs
index 0ff7cbb..7f74258 100644
--- a/imgui-sys-bindgen/src/lib.rs
+++ b/imgui-sys-bindgen/src/lib.rs
@@ -92,6 +92,7 @@ pub fn generate_bindings<P: AsRef<Path>>(cimgui_path: &P) -> Result<Bindings, Er
         .header_contents("cimgui.h", &header)
         .rust_target(RustTarget::Stable_1_36)
         .default_enum_style(EnumVariation::Consts)
+        .size_t_is_usize(true)
         .prepend_enum_name(false)
         .generate_comments(false)
         .layout_tests(true)
diff --git a/imgui-sys/src/bindings.rs b/imgui-sys/src/bindings.rs
index 4738e47..32f91ac 100644
--- a/imgui-sys/src/bindings.rs
+++ b/imgui-sys/src/bindings.rs
@@ -5,7 +5,6 @@
 #![allow(non_snake_case)]
 #![allow(clippy::all)]
 
-pub type size_t = ::std::os::raw::c_ulong;
 #[repr(C)]
 #[derive(Debug, Default, Copy, Clone, PartialEq)]
 pub struct ImVec2_Simple {
@@ -5155,12 +5154,12 @@ extern "C" {
 extern "C" {
     pub fn igDebugCheckVersionAndDataLayout(
         version_str: *const ::std::os::raw::c_char,
-        sz_io: size_t,
-        sz_style: size_t,
-        sz_vec2: size_t,
-        sz_vec4: size_t,
-        sz_drawvert: size_t,
-        sz_drawidx: size_t,
+        sz_io: usize,
+        sz_style: usize,
+        sz_vec2: usize,
+        sz_vec4: usize,
+        sz_drawvert: usize,
+        sz_drawidx: usize,
     ) -> bool;
 }
 extern "C" {
@@ -5921,7 +5920,7 @@ extern "C" {
     pub fn igInputText(
         label: *const ::std::os::raw::c_char,
         buf: *mut ::std::os::raw::c_char,
-        buf_size: size_t,
+        buf_size: usize,
         flags: ImGuiInputTextFlags,
         callback: ImGuiInputTextCallback,
         user_data: *mut ::std::os::raw::c_void,
@@ -5931,7 +5930,7 @@ extern "C" {
     pub fn igInputTextMultiline(
         label: *const ::std::os::raw::c_char,
         buf: *mut ::std::os::raw::c_char,
-        buf_size: size_t,
+        buf_size: usize,
         size: ImVec2,
         flags: ImGuiInputTextFlags,
         callback: ImGuiInputTextCallback,
@@ -5943,7 +5942,7 @@ extern "C" {
         label: *const ::std::os::raw::c_char,
         hint: *const ::std::os::raw::c_char,
         buf: *mut ::std::os::raw::c_char,
-        buf_size: size_t,
+        buf_size: usize,
         flags: ImGuiInputTextFlags,
         callback: ImGuiInputTextCallback,
         user_data: *mut ::std::os::raw::c_void,
@@ -6441,7 +6440,7 @@ extern "C" {
     pub fn igSetDragDropPayload(
         type_: *const ::std::os::raw::c_char,
         data: *const ::std::os::raw::c_void,
-        sz: size_t,
+        sz: usize,
         cond: ImGuiCond,
     ) -> bool;
 }
@@ -6636,19 +6635,19 @@ extern "C" {
     pub fn igLoadIniSettingsFromDisk(ini_filename: *const ::std::os::raw::c_char);
 }
 extern "C" {
-    pub fn igLoadIniSettingsFromMemory(ini_data: *const ::std::os::raw::c_char, ini_size: size_t);
+    pub fn igLoadIniSettingsFromMemory(ini_data: *const ::std::os::raw::c_char, ini_size: usize);
 }
 extern "C" {
     pub fn igSaveIniSettingsToDisk(ini_filename: *const ::std::os::raw::c_char);
 }
 extern "C" {
-    pub fn igSaveIniSettingsToMemory(out_ini_size: *mut size_t) -> *const ::std::os::raw::c_char;
+    pub fn igSaveIniSettingsToMemory(out_ini_size: *mut usize) -> *const ::std::os::raw::c_char;
 }
 extern "C" {
     pub fn igSetAllocatorFunctions(
         alloc_func: ::std::option::Option<
             unsafe extern "C" fn(
-                sz: size_t,
+                sz: usize,
                 user_data: *mut ::std::os::raw::c_void,
             ) -> *mut ::std::os::raw::c_void,
         >,
@@ -6662,7 +6661,7 @@ extern "C" {
     );
 }
 extern "C" {
-    pub fn igMemAlloc(size: size_t) -> *mut ::std::os::raw::c_void;
+    pub fn igMemAlloc(size: usize) -> *mut ::std::os::raw::c_void;
 }
 extern "C" {
     pub fn igMemFree(ptr: *mut ::std::os::raw::c_void);
diff --git a/src/context.rs b/src/context.rs
index 8fa39dd..48fb352 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -186,7 +186,7 @@ impl Context {
     }
     /// Loads settings from a string slice containing settings in .Ini file format
     pub fn load_ini_settings(&mut self, data: &str) {
-        unsafe { sys::igLoadIniSettingsFromMemory(data.as_ptr() as *const _, data.len() as u64) }
+        unsafe { sys::igLoadIniSettingsFromMemory(data.as_ptr() as *const _, data.len()) }
     }
     /// Saves settings to a mutable string buffer in .Ini file format
     pub fn save_ini_settings(&mut self, buf: &mut String) {
diff --git a/src/fonts/atlas.rs b/src/fonts/atlas.rs
index 4324d88..3209171 100644
--- a/src/fonts/atlas.rs
+++ b/src/fonts/atlas.rs
@@ -90,7 +90,7 @@ impl FontAtlas {
                 // We can't guarantee `data` is alive when the font atlas is built, so
                 // make a copy and move ownership of the data to the atlas
                 let data_copy = unsafe {
-                    let ptr = sys::igMemAlloc(data.len() as u64) as *mut u8;
+                    let ptr = sys::igMemAlloc(data.len()) as *mut u8;
                     assert!(!ptr.is_null());
                     slice::from_raw_parts_mut(ptr, data.len())
                 };
diff --git a/src/input_widget.rs b/src/input_widget.rs
index c9b2573..ea197d5 100644
--- a/src/input_widget.rs
+++ b/src/input_widget.rs
@@ -190,7 +190,7 @@ impl<'ui, 'p> InputText<'ui, 'p> {
             let result = sys::igInputText(
                 self.label.as_ptr(),
                 ptr,
-                capacity as u64,
+                capacity,
                 self.flags.bits(),
                 callback,
                 data,
@@ -240,7 +240,7 @@ impl<'ui, 'p> InputTextMultiline<'ui, 'p> {
             let result = sys::igInputTextMultiline(
                 self.label.as_ptr(),
                 ptr,
-                capacity as u64,
+                capacity,
                 self.size.into(),
                 self.flags.bits(),
                 callback,