diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3835283..f933828 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,7 +20,14 @@ jobs:
         with:
           go-version: ${{ matrix.go }}
       - name: Test
-        run: go test -v -race ./...
+        run: go test -v -race -coverprofile=coverage.out ./...
+      - name: Upload coverage to Codecov
+        if: matrix.os == 'ubuntu-latest'
+        uses: codecov/codecov-action@5a1091511ad55cbe89839c7260b706298ca349f7 # v5.5.1
+        with:
+          files: ./coverage.out
+        env:
+          CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
 
   lint:
     name: Lint
diff --git a/.gitignore b/.gitignore
index 884f556..a726663 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@ github-discover
 dist/
 .DS_Store
 demo/node_modules/
+coverage.out
diff --git a/README.md b/README.md
index 7995314..3f9ad13 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,7 @@
 # github-discover
 
 [![CI](https://github.com/atani/github-discover/actions/workflows/ci.yml/badge.svg)](https://github.com/atani/github-discover/actions/workflows/ci.yml)
+[![codecov](https://codecov.io/gh/atani/github-discover/branch/main/graph/badge.svg)](https://codecov.io/gh/atani/github-discover)
 [![Go Report Card](https://goreportcard.com/badge/github.com/atani/github-discover)](https://goreportcard.com/report/github.com/atani/github-discover)
 [![Go Reference](https://pkg.go.dev/badge/github.com/atani/github-discover.svg)](https://pkg.go.dev/github.com/atani/github-discover)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)