diff --git a/benchmark-compare.js b/benchmark-compare.js
index 16c8af71..f717d9e9 100644
--- a/benchmark-compare.js
+++ b/benchmark-compare.js
@@ -57,7 +57,7 @@ function updateReadme () {
 ${compareResults(true)}
 `
   const md = readFileSync('README.md', 'utf8')
-  writeFileSync('README.md', md.split('# Benchmarks')[0] + benchmarkMd, 'utf8')
+  writeFileSync('README.md', md.split('# Benchmarks', 1)[0] + benchmarkMd, 'utf8')
 }
 
 function compareResults (markdown) {
diff --git a/metrics/process-results.cjs b/metrics/process-results.cjs
index 427db7fd..cb0d1b94 100644
--- a/metrics/process-results.cjs
+++ b/metrics/process-results.cjs
@@ -18,7 +18,7 @@ function updateReadme (startupResults) {
 ${startupResults}
 `
   const md = fs.readFileSync('METRICS.md', 'utf8')
-  fs.writeFileSync('METRICS.md', md.split('# Metrics')[0] + benchmarkMd, 'utf8')
+  fs.writeFileSync('METRICS.md', md.split('# Metrics', 1)[0] + benchmarkMd, 'utf8')
 }
 
 const results = fs.readdirSync(__dirname).filter((x) => x.endsWith('.txt'))