diff --git a/cmd/devp2p/nodesetcmd.go b/cmd/devp2p/nodesetcmd.go
index 6fbc185ad8..e4a77d08ac 100644
--- a/cmd/devp2p/nodesetcmd.go
+++ b/cmd/devp2p/nodesetcmd.go
@@ -82,8 +82,8 @@ func showAttributeCounts(ns nodeSet) {
 		}
 	}
 
-	var keys []string
 	var maxlength int
+	keys := make([]string, 0, len(attrcount))
 	for key := range attrcount {
 		keys = append(keys, key)
 		if len(key) > maxlength {
diff --git a/cmd/evm/blockrunner.go b/cmd/evm/blockrunner.go
index 0275c019bc..9944c1fd39 100644
--- a/cmd/evm/blockrunner.go
+++ b/cmd/evm/blockrunner.go
@@ -76,7 +76,7 @@ func blockTestCmd(ctx *cli.Context) error {
 	}
 
 	// Run them in order
-	var keys []string
+	keys := make([]string, 0, len(tests))
 	for key := range tests {
 		keys = append(keys, key)
 	}
diff --git a/cmd/evm/internal/t8ntool/block.go b/cmd/evm/internal/t8ntool/block.go
index 62c8593a1d..057731c674 100644
--- a/cmd/evm/internal/t8ntool/block.go
+++ b/cmd/evm/internal/t8ntool/block.go
@@ -282,7 +282,7 @@ func readInput(ctx *cli.Context) (*bbInput, error) {
 	}
 	// Deserialize rlp txs and ommers
 	var (
-		ommers = []*types.Header{}
+		ommers = make([]*types.Header, 0, len(inputData.OmmersRlp))
 		txs    = []*types.Transaction{}
 	)
 	if inputData.TxRlp != "" {
diff --git a/trie/proof_test.go b/trie/proof_test.go
index fab3a97650..52de9d037c 100644
--- a/trie/proof_test.go
+++ b/trie/proof_test.go
@@ -832,7 +832,7 @@ func decreaseKey(key []byte) []byte {
 
 func BenchmarkProve(b *testing.B) {
 	trie, vals := randomTrie(100)
-	var keys []string
+	keys := make([]string, 0, len(vals))
 	for k := range vals {
 		keys = append(keys, k)
 	}
@@ -850,8 +850,8 @@ func BenchmarkProve(b *testing.B) {
 func BenchmarkVerifyProof(b *testing.B) {
 	trie, vals := randomTrie(100)
 	root := trie.Hash()
-	var keys []string
 	var proofs []*memorydb.Database
+	keys := make([]string, 0, len(vals))
 	for k := range vals {
 		keys = append(keys, k)
 		proof := memorydb.New()
diff --git a/trie/tracer_test.go b/trie/tracer_test.go
index 27e42d497a..0050dab669 100644
--- a/trie/tracer_test.go
+++ b/trie/tracer_test.go
@@ -164,7 +164,7 @@ func testAccessList(t *testing.T, vals []struct{ k, v string }) {
 	parent = root
 	trie, _ = New(TrieID(root), db)
 	orig = trie.Copy()
-	var keys []string
+	keys := make([]string, 0, 30)
 	for i := 0; i < 30; i++ {
 		key := randBytes(32)
 		keys = append(keys, string(key))