diff --git a/library/ccm.c b/library/ccm.c
index 3edfba3..675783e 100644
--- a/library/ccm.c
+++ b/library/ccm.c
@@ -144,7 +144,7 @@
     unsigned char i;
     size_t len_left, olen;
 
-    /* length calulcation can be done only after both
+    /* length calculation can be done only after both
      * mbedtls_ccm_starts() and mbedtls_ccm_set_lengths() have been executed
      */
     if( !(ctx->state & CCM_STATE__STARTED) || !(ctx->state & CCM_STATE__LENGTHS_SET) )