diff --git a/Thirdweb.Tests/Thirdweb.Transactions.Tests.cs b/Thirdweb.Tests/Thirdweb.Transactions.Tests.cs
new file mode 100644
index 0000000..e055bcb
--- /dev/null
+++ b/Thirdweb.Tests/Thirdweb.Transactions.Tests.cs
@@ -0,0 +1,88 @@
+using System.Numerics;
+
+namespace Thirdweb.Tests;
+
+public class TransactionTests : BaseTests
+{
+    public TransactionTests(ITestOutputHelper output)
+        : base(output) { }
+
+    [Fact]
+    public async Task WaitForTransactionReceipt()
+    {
+        var client = ThirdwebClient.Create(secretKey: _secretKey);
+        var chainId = 421614;
+        var normalTxHash = "0x5a0b6cdb01ecfb25b368d3de1ac844414980ee3c330ec8c1435117b75027b5d7";
+        var failedTxHash = "0xd2840219ffe172377c8a455c13d95e4dca204d5c0dd72232093e092eef412488";
+        var aaTxHash = "0xbf76bd85e1759cf5cf9f4c7c52e76a74d32687f0b516017ff28192d04df50782";
+        var aaSilentRevertTxHash = "0x8ada86c63846da7a3f91b8c8332de03f134e7619886425df858ee5400a9d9958";
+
+        var normalReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, normalTxHash);
+        Assert.NotNull(normalReceipt);
+
+        var failedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, failedTxHash));
+        Assert.Equal($"Transaction {failedTxHash} execution reverted.", failedReceipt.Message);
+
+        var aaReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaTxHash);
+        Assert.NotNull(aaReceipt);
+
+        var aaFailedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaSilentRevertTxHash));
+        Assert.StartsWith($"Transaction {aaSilentRevertTxHash} execution silently reverted", aaFailedReceipt.Message);
+    }
+
+    [Fact]
+    public async Task WaitForTransactionReceipt_AAReasonString()
+    {
+        var client = ThirdwebClient.Create(secretKey: _secretKey);
+        var chainId = 84532;
+        var aaSilentRevertTxHashWithReason = "0x5374743bbb749df47a279ac21e6ed472c30cd471923a7bc78db6a40e1b6924de";
+        var aaFailedReceiptWithReason = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaSilentRevertTxHashWithReason));
+        Assert.StartsWith($"Transaction {aaSilentRevertTxHashWithReason} execution silently reverted:", aaFailedReceiptWithReason.Message);
+    }
+
+    [Fact]
+    public async Task WaitForTransactionReceipt_CancellationToken()
+    {
+        var client = ThirdwebClient.Create(secretKey: _secretKey);
+        var chainId = 421614;
+        var normalTxHash = "0x5a0b6cdb01ecfb25b368d3de1ac844414980ee3c330ec8c1435117b75027b5d7";
+        var failedTxHash = "0xd2840219ffe172377c8a455c13d95e4dca204d5c0dd72232093e092eef412488";
+        var aaTxHash = "0xbf76bd85e1759cf5cf9f4c7c52e76a74d32687f0b516017ff28192d04df50782";
+        var aaSilentRevertTxHash = "0x8ada86c63846da7a3f91b8c8332de03f134e7619886425df858ee5400a9d9958";
+
+        var cts = new CancellationTokenSource();
+        cts.CancelAfter(10000);
+        var normalReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, normalTxHash, cts.Token);
+        Assert.NotNull(normalReceipt);
+
+        cts = new CancellationTokenSource();
+        cts.CancelAfter(10000);
+        var failedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, failedTxHash, cts.Token));
+        Assert.Equal($"Transaction {failedTxHash} execution reverted.", failedReceipt.Message);
+
+        cts = new CancellationTokenSource();
+        cts.CancelAfter(10000);
+        var aaReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaTxHash, cts.Token);
+        Assert.NotNull(aaReceipt);
+
+        cts = new CancellationTokenSource();
+        cts.CancelAfter(10000);
+        var aaFailedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaSilentRevertTxHash, cts.Token));
+        Assert.StartsWith($"Transaction {aaSilentRevertTxHash} execution silently reverted", aaFailedReceipt.Message);
+
+        var infiniteTxHash = "0x55181384a4b908ddf6311cf0eb55ea0aa2b1ef4d9e0cc047eab9051fec284958";
+        cts = new CancellationTokenSource();
+        cts.CancelAfter(1);
+        var infiniteReceipt = await Assert.ThrowsAsync<TaskCanceledException>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, infiniteTxHash, cts.Token));
+        Assert.Equal("A task was canceled.", infiniteReceipt.Message);
+
+        cts = new CancellationTokenSource();
+        var infiniteReceipt2 = Assert.ThrowsAsync<TaskCanceledException>(() => ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, infiniteTxHash, cts.Token));
+        await Task.Delay(2000);
+        cts.Cancel();
+        Assert.Equal("A task was canceled.", (await infiniteReceipt2).Message);
+
+        var aaReceipt2 = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaTxHash, CancellationToken.None);
+        Assert.NotNull(aaReceipt2);
+    }
+}
diff --git a/Thirdweb.Tests/Thirdweb.Utils.Tests.cs b/Thirdweb.Tests/Thirdweb.Utils.Tests.cs
index 56115f5..475b90b 100644
--- a/Thirdweb.Tests/Thirdweb.Utils.Tests.cs
+++ b/Thirdweb.Tests/Thirdweb.Utils.Tests.cs
@@ -20,85 +20,6 @@ public void HexConcat()
         Assert.Equal("0x1234567890AB", Utils.HexConcat(hexStrings));
     }
 
-    [Fact]
-    public async Task GetTransactionReceipt()
-    {
-        var client = ThirdwebClient.Create(secretKey: _secretKey);
-        var chainId = 421614;
-        var normalTxHash = "0x5a0b6cdb01ecfb25b368d3de1ac844414980ee3c330ec8c1435117b75027b5d7";
-        var failedTxHash = "0xd2840219ffe172377c8a455c13d95e4dca204d5c0dd72232093e092eef412488";
-        var aaTxHash = "0xbf76bd85e1759cf5cf9f4c7c52e76a74d32687f0b516017ff28192d04df50782";
-        var aaSilentRevertTxHash = "0x8ada86c63846da7a3f91b8c8332de03f134e7619886425df858ee5400a9d9958";
-
-        var normalReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, normalTxHash);
-        Assert.NotNull(normalReceipt);
-
-        var failedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, failedTxHash));
-        Assert.Equal($"Transaction {failedTxHash} execution reverted.", failedReceipt.Message);
-
-        var aaReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaTxHash);
-        Assert.NotNull(aaReceipt);
-
-        var aaFailedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaSilentRevertTxHash));
-        Assert.StartsWith($"Transaction {aaSilentRevertTxHash} execution silently reverted", aaFailedReceipt.Message);
-    }
-
-    [Fact]
-    public async Task GetTransactionReceipt_AAReasonString()
-    {
-        var client = ThirdwebClient.Create(secretKey: _secretKey);
-        var chainId = 84532;
-        var aaSilentRevertTxHashWithReason = "0x5374743bbb749df47a279ac21e6ed472c30cd471923a7bc78db6a40e1b6924de";
-        var aaFailedReceiptWithReason = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaSilentRevertTxHashWithReason));
-        Assert.StartsWith($"Transaction {aaSilentRevertTxHashWithReason} execution silently reverted:", aaFailedReceiptWithReason.Message);
-    }
-
-    [Fact]
-    public async Task GetTransactionReceipt_CancellationToken()
-    {
-        var client = ThirdwebClient.Create(secretKey: _secretKey);
-        var chainId = 421614;
-        var normalTxHash = "0x5a0b6cdb01ecfb25b368d3de1ac844414980ee3c330ec8c1435117b75027b5d7";
-        var failedTxHash = "0xd2840219ffe172377c8a455c13d95e4dca204d5c0dd72232093e092eef412488";
-        var aaTxHash = "0xbf76bd85e1759cf5cf9f4c7c52e76a74d32687f0b516017ff28192d04df50782";
-        var aaSilentRevertTxHash = "0x8ada86c63846da7a3f91b8c8332de03f134e7619886425df858ee5400a9d9958";
-
-        var cts = new CancellationTokenSource();
-        cts.CancelAfter(10000);
-        var normalReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, normalTxHash, cts.Token);
-        Assert.NotNull(normalReceipt);
-
-        cts = new CancellationTokenSource();
-        cts.CancelAfter(10000);
-        var failedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, failedTxHash, cts.Token));
-        Assert.Equal($"Transaction {failedTxHash} execution reverted.", failedReceipt.Message);
-
-        cts = new CancellationTokenSource();
-        cts.CancelAfter(10000);
-        var aaReceipt = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaTxHash, cts.Token);
-        Assert.NotNull(aaReceipt);
-
-        cts = new CancellationTokenSource();
-        cts.CancelAfter(10000);
-        var aaFailedReceipt = await Assert.ThrowsAsync<Exception>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaSilentRevertTxHash, cts.Token));
-        Assert.StartsWith($"Transaction {aaSilentRevertTxHash} execution silently reverted", aaFailedReceipt.Message);
-
-        var infiniteTxHash = "0x55181384a4b908ddf6311cf0eb55ea0aa2b1ef4d9e0cc047eab9051fec284958";
-        cts = new CancellationTokenSource();
-        cts.CancelAfter(1);
-        var infiniteReceipt = await Assert.ThrowsAsync<TaskCanceledException>(async () => await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, infiniteTxHash, cts.Token));
-        Assert.Equal("A task was canceled.", infiniteReceipt.Message);
-
-        cts = new CancellationTokenSource();
-        var infiniteReceipt2 = Assert.ThrowsAsync<TaskCanceledException>(() => ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, infiniteTxHash, cts.Token));
-        await Task.Delay(2000);
-        cts.Cancel();
-        Assert.Equal("A task was canceled.", (await infiniteReceipt2).Message);
-
-        var aaReceipt2 = await ThirdwebTransaction.WaitForTransactionReceipt(client, chainId, aaTxHash, CancellationToken.None);
-        Assert.NotNull(aaReceipt2);
-    }
-
     [Fact]
     public void HashPrefixedMessage()
     {
@@ -274,4 +195,11 @@ public void FormatERC20_SmallFractionalWei()
         var fractionalWei = "10";
         Assert.Equal("0.0000", Utils.FormatERC20(fractionalWei, 4));
     }
+
+    [Fact]
+    public void FormatERC20_ThrowsOnInvalidWei()
+    {
+        var invalidWei = "not_a_number";
+        Assert.Throws<ArgumentException>(() => Utils.FormatERC20(invalidWei, 4));
+    }
 }
diff --git a/Thirdweb/Thirdweb.Utils/Utils.cs b/Thirdweb/Thirdweb.Utils/Utils.cs
index 04fb562..9d3d94a 100644
--- a/Thirdweb/Thirdweb.Utils/Utils.cs
+++ b/Thirdweb/Thirdweb.Utils/Utils.cs
@@ -123,15 +123,18 @@ public static string ToEth(this string wei, int decimalsToDisplay = 4, bool addC
 
         public static string FormatERC20(this string wei, int decimalsToDisplay = 4, int decimals = 18, bool addCommas = false)
         {
-            decimals = decimals == 0 ? 18 : decimals;
             if (!BigInteger.TryParse(wei, out var weiBigInt))
             {
                 throw new ArgumentException("Invalid wei value.");
             }
 
             var eth = (double)weiBigInt / Math.Pow(10.0, decimals);
-            var format = addCommas ? "#,0." : "#0.";
-            format += new string('0', decimalsToDisplay);
+            var format = addCommas ? "#,0" : "#0";
+            if (decimalsToDisplay > 0)
+            {
+                format += ".";
+                format += new string('0', decimalsToDisplay);
+            }
 
             return eth.ToString(format);
         }