diff --git a/fixtures/fizz/README.md b/fixtures/fizz/README.md
index 63acd3ddc545d..7cd118b8947ba 100644
--- a/fixtures/fizz/README.md
+++ b/fixtures/fizz/README.md
@@ -1,6 +1,6 @@
 # Fizz Fixtures
 
-A set of basic tests for Fizz primarily focussed on baseline perfomrance of legacy renderToString and streaming implementations.
+A set of basic tests for Fizz primarily focussed on baseline performance of legacy renderToString and streaming implementations.
 
 ## Setup
 
diff --git a/packages/react-devtools-core/README.md b/packages/react-devtools-core/README.md
index 4ee323fc99107..af6b3a1264eff 100644
--- a/packages/react-devtools-core/README.md
+++ b/packages/react-devtools-core/README.md
@@ -90,7 +90,7 @@ Set the DOM element DevTools UI should be rendered into on initialization.
 _Optional_ callback to be notified when DevTools `WebSocket` closes (or errors).
 
 #### `setProjectRoots(roots: Array<string>)`
-_Optional_ set of root directores for source files. These roots can be used to open an inspected component's source code using an IDE.
+_Optional_ set of root directories for source files. These roots can be used to open an inspected component's source code using an IDE.
 
 #### `setStatusListener(callback: Function)`
 _Optional_ callback to be notified of socket server events (e.g. initialized, errored, connected).