diff --git a/docs/library/machine.RTC.rst b/docs/library/machine.RTC.rst
index d5a4f390b5..ae5446ef74 100644
--- a/docs/library/machine.RTC.rst
+++ b/docs/library/machine.RTC.rst
@@ -4,7 +4,7 @@
 class RTC -- real time clock
 ============================
 
-The RTC is and independent clock that keeps track of the date
+The RTC is an independent clock that keeps track of the date
 and time.
 
 Example usage::
diff --git a/docs/library/pyb.RTC.rst b/docs/library/pyb.RTC.rst
index 4c736597cf..c477e7f035 100644
--- a/docs/library/pyb.RTC.rst
+++ b/docs/library/pyb.RTC.rst
@@ -4,7 +4,7 @@
 class RTC -- real time clock
 ============================
 
-The RTC is and independent clock that keeps track of the date
+The RTC is an independent clock that keeps track of the date
 and time.
 
 Example usage::
diff --git a/ports/stm32/rtc.c b/ports/stm32/rtc.c
index bd898d4558..02b0f2dbd1 100644
--- a/ports/stm32/rtc.c
+++ b/ports/stm32/rtc.c
@@ -43,7 +43,7 @@
 /// \moduleref pyb
 /// \class RTC - real time clock
 ///
-/// The RTC is and independent clock that keeps track of the date
+/// The RTC is an independent clock that keeps track of the date
 /// and time.
 ///
 /// Example usage: