diff --git a/cmd/utils/export_test.go b/cmd/utils/export_test.go
index b70d2451c6..d1a004d9b7 100644
--- a/cmd/utils/export_test.go
+++ b/cmd/utils/export_test.go
@@ -54,8 +54,8 @@ func (iter *testIterator) Next() (byte, []byte, []byte, bool) {
 	if iter.index == 42 {
 		iter.index += 1
 	}
-	return OpBatchAdd, []byte(fmt.Sprintf("key-%04d", iter.index)),
-		[]byte(fmt.Sprintf("value %d", iter.index)), true
+	return OpBatchAdd, fmt.Appendf(nil, "key-%04d", iter.index),
+		fmt.Appendf(nil, "value %d", iter.index), true
 }
 
 func (iter *testIterator) Release() {}
@@ -72,7 +72,7 @@ func testExport(t *testing.T, f string) {
 	}
 	// verify
 	for i := 0; i < 1000; i++ {
-		v, err := db.Get([]byte(fmt.Sprintf("key-%04d", i)))
+		v, err := db.Get(fmt.Appendf(nil, "key-%04d", i))
 		if (i < 5 || i == 42) && err == nil {
 			t.Fatalf("expected no element at idx %d, got '%v'", i, string(v))
 		}
@@ -85,7 +85,7 @@ func testExport(t *testing.T, f string) {
 			}
 		}
 	}
-	v, err := db.Get([]byte(fmt.Sprintf("key-%04d", 1000)))
+	v, err := db.Get(fmt.Appendf(nil, "key-%04d", 1000))
 	if err == nil {
 		t.Fatalf("expected no element at idx %d, got '%v'", 1000, string(v))
 	}
@@ -120,7 +120,7 @@ func (iter *deletionIterator) Next() (byte, []byte, []byte, bool) {
 	if iter.index == 42 {
 		iter.index += 1
 	}
-	return OpBatchDel, []byte(fmt.Sprintf("key-%04d", iter.index)), nil, true
+	return OpBatchDel, fmt.Appendf(nil, "key-%04d", iter.index), nil, true
 }
 
 func (iter *deletionIterator) Release() {}
@@ -132,14 +132,14 @@ func testDeletion(t *testing.T, f string) {
 	}
 	db := rawdb.NewMemoryDatabase()
 	for i := 0; i < 1000; i++ {
-		db.Put([]byte(fmt.Sprintf("key-%04d", i)), []byte(fmt.Sprintf("value %d", i)))
+		db.Put(fmt.Appendf(nil, "key-%04d", i), fmt.Appendf(nil, "value %d", i))
 	}
 	err = ImportLDBData(db, f, 5, make(chan struct{}))
 	if err != nil {
 		t.Fatal(err)
 	}
 	for i := 0; i < 1000; i++ {
-		v, err := db.Get([]byte(fmt.Sprintf("key-%04d", i)))
+		v, err := db.Get(fmt.Appendf(nil, "key-%04d", i))
 		if i < 5 || i == 42 {
 			if err != nil {
 				t.Fatalf("expected element at idx %d, got '%v'", i, err)
diff --git a/common/math/big.go b/common/math/big.go
index 825f4baec9..493c2b7861 100644
--- a/common/math/big.go
+++ b/common/math/big.go
@@ -72,7 +72,7 @@ func (i *HexOrDecimal256) MarshalText() ([]byte, error) {
 	if i == nil {
 		return []byte("0x0"), nil
 	}
-	return []byte(fmt.Sprintf("%#x", (*big.Int)(i))), nil
+	return fmt.Appendf(nil, "%#x", (*big.Int)(i)), nil
 }
 
 // Decimal256 unmarshals big.Int as a decimal string. When unmarshalling,
diff --git a/common/math/integer.go b/common/math/integer.go
index 25ced87053..dfcb0aecc4 100644
--- a/common/math/integer.go
+++ b/common/math/integer.go
@@ -48,7 +48,7 @@ func (i *HexOrDecimal64) UnmarshalText(input []byte) error {
 
 // MarshalText implements encoding.TextMarshaler.
 func (i HexOrDecimal64) MarshalText() ([]byte, error) {
-	return []byte(fmt.Sprintf("%#x", uint64(i))), nil
+	return fmt.Appendf(nil, "%#x", uint64(i)), nil
 }
 
 // ParseUint64 parses s as an integer in decimal or hexadecimal syntax.
diff --git a/core/state/snapshot/generate_test.go b/core/state/snapshot/generate_test.go
index 661610840a..3de7735ef8 100644
--- a/core/state/snapshot/generate_test.go
+++ b/core/state/snapshot/generate_test.go
@@ -655,7 +655,7 @@ func testGenerateWithManyExtraAccounts(t *testing.T, scheme string) {
 		for i := 0; i < 1000; i++ {
 			acc := &types.StateAccount{Balance: uint256.NewInt(uint64(i)), Root: types.EmptyRootHash, CodeHash: types.EmptyCodeHash.Bytes()}
 			val, _ := rlp.EncodeToBytes(acc)
-			key := hashData([]byte(fmt.Sprintf("acc-%d", i)))
+			key := hashData(fmt.Appendf(nil, "acc-%d", i))
 			rawdb.WriteAccountSnapshot(helper.diskdb, key, val)
 		}
 	}
diff --git a/core/state/snapshot/iterator_test.go b/core/state/snapshot/iterator_test.go
index b9fe370b86..2e882f484e 100644
--- a/core/state/snapshot/iterator_test.go
+++ b/core/state/snapshot/iterator_test.go
@@ -329,27 +329,27 @@ func TestAccountIteratorTraversalValues(t *testing.T) {
 		h = make(map[common.Hash][]byte)
 	)
 	for i := byte(2); i < 0xff; i++ {
-		a[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 0, i))
+		a[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 0, i)
 		if i > 20 && i%2 == 0 {
-			b[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 1, i))
+			b[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 1, i)
 		}
 		if i%4 == 0 {
-			c[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 2, i))
+			c[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 2, i)
 		}
 		if i%7 == 0 {
-			d[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 3, i))
+			d[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 3, i)
 		}
 		if i%8 == 0 {
-			e[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 4, i))
+			e[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 4, i)
 		}
 		if i > 50 || i < 85 {
-			f[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 5, i))
+			f[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 5, i)
 		}
 		if i%64 == 0 {
-			g[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 6, i))
+			g[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 6, i)
 		}
 		if i%128 == 0 {
-			h[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 7, i))
+			h[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 7, i)
 		}
 	}
 	// Assemble a stack of snapshots from the account layers
@@ -428,27 +428,27 @@ func TestStorageIteratorTraversalValues(t *testing.T) {
 		h = make(map[common.Hash][]byte)
 	)
 	for i := byte(2); i < 0xff; i++ {
-		a[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 0, i))
+		a[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 0, i)
 		if i > 20 && i%2 == 0 {
-			b[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 1, i))
+			b[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 1, i)
 		}
 		if i%4 == 0 {
-			c[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 2, i))
+			c[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 2, i)
 		}
 		if i%7 == 0 {
-			d[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 3, i))
+			d[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 3, i)
 		}
 		if i%8 == 0 {
-			e[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 4, i))
+			e[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 4, i)
 		}
 		if i > 50 || i < 85 {
-			f[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 5, i))
+			f[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 5, i)
 		}
 		if i%64 == 0 {
-			g[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 6, i))
+			g[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 6, i)
 		}
 		if i%128 == 0 {
-			h[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 7, i))
+			h[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 7, i)
 		}
 	}
 	// Assemble a stack of snapshots from the account layers
diff --git a/p2p/nat/nat.go b/p2p/nat/nat.go
index 5f7af7424d..a0ddb3b29b 100644
--- a/p2p/nat/nat.go
+++ b/p2p/nat/nat.go
@@ -140,7 +140,7 @@ type ExtIP net.IP
 
 func (n ExtIP) ExternalIP() (net.IP, error)  { return net.IP(n), nil }
 func (n ExtIP) String() string               { return fmt.Sprintf("ExtIP(%v)", net.IP(n)) }
-func (n ExtIP) MarshalText() ([]byte, error) { return []byte(fmt.Sprintf("extip:%v", net.IP(n))), nil }
+func (n ExtIP) MarshalText() ([]byte, error) { return fmt.Appendf(nil, "extip:%v", net.IP(n)), nil }
 
 // These do nothing.
 
diff --git a/p2p/nat/natpmp.go b/p2p/nat/natpmp.go
index b8f59ee890..4a9644ac1a 100644
--- a/p2p/nat/natpmp.go
+++ b/p2p/nat/natpmp.go
@@ -71,7 +71,7 @@ func (n *pmp) DeleteMapping(protocol string, extport, intport int) (err error) {
 }
 
 func (n *pmp) MarshalText() ([]byte, error) {
-	return []byte(fmt.Sprintf("natpmp:%v", n.gw)), nil
+	return fmt.Appendf(nil, "natpmp:%v", n.gw), nil
 }
 
 func discoverPMP() Interface {
diff --git a/signer/core/apitypes/signed_data_internal_test.go b/signer/core/apitypes/signed_data_internal_test.go
index 1a14b35ef2..bee9f1c351 100644
--- a/signer/core/apitypes/signed_data_internal_test.go
+++ b/signer/core/apitypes/signed_data_internal_test.go
@@ -282,7 +282,7 @@ func TestTypedDataArrayValidate(t *testing.T) {
 			messageHash, tErr := td.HashStruct(td.PrimaryType, td.Message)
 			assert.NoError(t, tErr, "failed to hash message: %v", tErr)
 
-			digest := crypto.Keccak256Hash([]byte(fmt.Sprintf("%s%s%s", "\x19\x01", string(domainSeparator), string(messageHash))))
+			digest := crypto.Keccak256Hash(fmt.Appendf(nil, "%s%s%s", "\x19\x01", string(domainSeparator), string(messageHash)))
 			assert.Equal(t, tc.Digest, digest.String(), "digest doesn't not match")
 
 			assert.NoError(t, td.validate(), "validation failed", tErr)
diff --git a/signer/core/signed_data_test.go b/signer/core/signed_data_test.go
index b6c080736c..001f6b6838 100644
--- a/signer/core/signed_data_test.go
+++ b/signer/core/signed_data_test.go
@@ -369,7 +369,7 @@ func sign(typedData apitypes.TypedData) ([]byte, []byte, error) {
 	if err != nil {
 		return nil, nil, err
 	}
-	rawData := []byte(fmt.Sprintf("\x19\x01%s%s", string(domainSeparator), string(typedDataHash)))
+	rawData := fmt.Appendf(nil, "\x19\x01%s%s", string(domainSeparator), string(typedDataHash))
 	sighash := crypto.Keccak256(rawData)
 	return typedDataHash, sighash, nil
 }
diff --git a/triedb/pathdb/iterator_test.go b/triedb/pathdb/iterator_test.go
index 05a166d1b6..3894118034 100644
--- a/triedb/pathdb/iterator_test.go
+++ b/triedb/pathdb/iterator_test.go
@@ -371,27 +371,27 @@ func TestAccountIteratorTraversalValues(t *testing.T) {
 		h = make(map[common.Hash][]byte)
 	)
 	for i := byte(2); i < 0xff; i++ {
-		a[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 0, i))
+		a[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 0, i)
 		if i > 20 && i%2 == 0 {
-			b[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 1, i))
+			b[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 1, i)
 		}
 		if i%4 == 0 {
-			c[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 2, i))
+			c[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 2, i)
 		}
 		if i%7 == 0 {
-			d[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 3, i))
+			d[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 3, i)
 		}
 		if i%8 == 0 {
-			e[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 4, i))
+			e[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 4, i)
 		}
 		if i > 50 || i < 85 {
-			f[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 5, i))
+			f[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 5, i)
 		}
 		if i%64 == 0 {
-			g[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 6, i))
+			g[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 6, i)
 		}
 		if i%128 == 0 {
-			h[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 7, i))
+			h[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 7, i)
 		}
 	}
 	// Assemble a stack of snapshots from the account layers
@@ -480,27 +480,27 @@ func TestStorageIteratorTraversalValues(t *testing.T) {
 		h = make(map[common.Hash][]byte)
 	)
 	for i := byte(2); i < 0xff; i++ {
-		a[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 0, i))
+		a[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 0, i)
 		if i > 20 && i%2 == 0 {
-			b[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 1, i))
+			b[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 1, i)
 		}
 		if i%4 == 0 {
-			c[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 2, i))
+			c[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 2, i)
 		}
 		if i%7 == 0 {
-			d[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 3, i))
+			d[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 3, i)
 		}
 		if i%8 == 0 {
-			e[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 4, i))
+			e[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 4, i)
 		}
 		if i > 50 || i < 85 {
-			f[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 5, i))
+			f[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 5, i)
 		}
 		if i%64 == 0 {
-			g[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 6, i))
+			g[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 6, i)
 		}
 		if i%128 == 0 {
-			h[common.Hash{i}] = []byte(fmt.Sprintf("layer-%d, key %d", 7, i))
+			h[common.Hash{i}] = fmt.Appendf(nil, "layer-%d, key %d", 7, i)
 		}
 	}
 	// Assemble a stack of snapshots from the account layers