diff --git a/doc/api.md b/doc/api.md
index 3083ff0b..9fbc9f2f 100644
--- a/doc/api.md
+++ b/doc/api.md
@@ -709,43 +709,52 @@ following differences:
   (ignoring redundant digits and sign in exponent) and may procude more
   decimal digits than necessary.
 
-## Compile-Time Configuration
+## Configuration Options
 
-{fmt} provides configuration via CMake options and preprocessor macros to enable or disable features and to optimize for binary size. You can set CMake options when generating your build system (e.g. `-DFMT_OS=OFF`) and define macros or pass them to your compiler (e.g. `-DFMT_USE_EXCEPTIONS=0`).
+{fmt} provides configuration via CMake options and preprocessor macros to
+enable or disable features and to optimize for binary size. For example, you
+can disable OS-specific APIs defined in `fmt/os.h` with `-DFMT_OS=OFF` when
+configuring CMake.
 
-### Available Options
+### CMake Options
 
-| Option               | Type         | Default                                  | Description                                                                                                                         |
-| -------------------- | ------------ | ---------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------- |
-| Header-Only Mode     | CMake target | `fmt::fmt`                               | Enable header-only usage by linking the `fmt::fmt-header-only` target.                                                              |
-| `FMT_HEADER_ONLY`    | 0 / 1        | 0                                        | Enables header-only mode when set to 1 (CMake target `fmt::fmt-header-only` defines it); disable with 0 for library mode.           |
-| `FMT_OS`             | ON / OFF     | ON                                       | Enables OS-specific APIs (`fmt/os.h`); disable with OFF.                                                                            |
-| `FMT_UNICODE`        | ON / OFF     | ON                                       | Enables Unicode support; disable with OFF.                                                                                          |
-| `FMT_USE_EXCEPTIONS` | 0 / 1        | 1 (0 if compiled with `-fno-exceptions`) | Enables exception-based error handling; disable with 0.                                                                             |
-| `FMT_BUILTIN_TYPES`  | 0 / 1        | 1                                        | Enables built-in type formatters; disable with 0.                                                                                   |
-| `FMT_OPTIMIZE_SIZE`  | 0 / 1 / 2    | 0                                        | Controls size-optimized routines: 0 = off, 1 = size optimization, >1 = aggressive size optimization disabling format-string checks. |
-| `FMT_USE_LOCALE`     | 0 / 1        | 1 (0 when `FMT_OPTIMIZE_SIZE > 1`)       | Enables locale-dependent formatting; disable with 0.                                                                                |
-| `FMT_THROW(x)`       | macro        | `throw x` (or `abort`)                   | Defines error handling via macro (not a toggle flag): if exceptions enabled, `throw x`; otherwise, `fmt::assert_fail(...)`.         |
+- **`FMT_OS`**: When set to `OFF`, disables OS-specific APIs (`fmt/os.h`).
+- **`FMT_UNICODE`**: When set of `OFF`, disables Unicode support on
+  Windows/MSVC. Unicode support is always enabled on other platforms.
 
-### Size Optimization Recipe
+### Macros
 
-To minimize your binary footprint, use the following CMake configuration and compile definitions:
+- **`FMT_HEADER_ONLY`**: Enables the header-only mode when defined. It is an
+  alternative to using the `fmt::fmt-header-only` CMake target.
+  Default: not defined.
 
-```cmake
-# Link to the header-only target
-target_link_libraries(${PROJECT_NAME} PRIVATE fmt::fmt-header-only)
-# Disable OS-specific APIs
-set(FMT_OS OFF CACHE BOOL "" FORCE)
-# Disable Unicode support
-set(FMT_UNICODE OFF CACHE BOOL "" FORCE)
-# Add compile definitions to your target
-target_compile_definitions(
-    ${PROJECT_NAME}
-    PRIVATE
-    FMT_USE_EXCEPTIONS=0
-    FMT_OS=0
-    FMT_BUILTIN_TYPES=0
-    FMT_OPTIMIZE_SIZE=2
-    FMT_USE_LOCALE=0
-)
-```
+- **`FMT_USE_EXCEPTIONS`**: Disables the use of exceptions when set to `0`.
+  Default: `1` (`0` if compiled with `-fno-exceptions`).
+
+- **`FMT_USE_LOCALE`**: When set to `0`, disables locale support.
+  Default: `1` (`0` when `FMT_OPTIMIZE_SIZE > 1`).
+
+- **`FMT_CUSTOM_ASSERT_FAIL`**: When set to `1`, allows users to provide a
+  custom `fmt::assert_fail` function which is called on assertion failures and,
+  if exceptions are disabled, on runtime errors. Default: `0`.
+
+- **`FMT_BUILTIN_TYPES`**: When set to `0`, disables built-in handling of
+  arithmetic and string types other than `int`. This reduces library size at
+  the cost of per-call overhead. Default: `1`.
+
+- **`FMT_OPTIMIZE_SIZE`**: Controls binary size optimizations:
+    - `0` - off (default)
+    - `1` - disables locale support and applies some optimizations
+    - `2` - disables some Unicode features, named arguments and applies more
+      aggresive optimizations
+
+### Binary Size Optimization
+
+To minimize the binary footprint of {fmt} as much as possible at the cost of
+some features, you can use the following configuration:
+
+- CMake options:
+    - `FMT_OS=OFF`
+- Macros:
+    - `FMT_BUILTIN_TYPES=0`
+    - `FMT_OPTIMIZE_SIZE=2`