diff --git a/internal/jsnum/pseudobigint_test.go b/internal/jsnum/pseudobigint_test.go
index fbd2bcaacd..db34ae4c5e 100644
--- a/internal/jsnum/pseudobigint_test.go
+++ b/internal/jsnum/pseudobigint_test.go
@@ -31,7 +31,41 @@ func TestParsePseudoBigInt(t *testing.T) {
 		}
 	})
 
-	// TODO(jakebailey): tests for other bases
+	t.Run("parse non-decimal bases (small numbers)", func(t *testing.T) {
+		t.Parallel()
+
+		type tc struct {
+			lit string
+			out string
+		}
+		cases := []tc{
+			// binary
+			{lit: "0b0n", out: "0"},
+			{lit: "0b1n", out: "1"},
+			{lit: "0b1010n", out: "10"},
+			{lit: "0b1010_0101n", out: "165"},
+			{lit: "0B1101n", out: "13"}, // uppercase prefix
+
+			// octal
+			{lit: "0o0n", out: "0"},
+			{lit: "0o7n", out: "7"},
+			{lit: "0o755n", out: "493"},
+			{lit: "0o7_5_5n", out: "493"},
+			{lit: "0O12n", out: "10"}, // uppercase prefix
+
+			// hex
+			{lit: "0x0n", out: "0"},
+			{lit: "0xFn", out: "15"},
+			{lit: "0xFFn", out: "255"},
+			{lit: "0xF_Fn", out: "255"},
+			{lit: "0X1Fn", out: "31"}, // uppercase prefix
+		}
+
+		for _, c := range cases {
+			got := ParsePseudoBigInt(c.lit)
+			assert.Equal(t, got, c.out, "literal: %q", c.lit)
+		}
+	})
 
 	t.Run("can parse large literals", func(t *testing.T) {
 		t.Parallel()