diff --git a/d2compiler/compile.go b/d2compiler/compile.go
index 1c83edf99..2e85a27be 100644
--- a/d2compiler/compile.go
+++ b/d2compiler/compile.go
@@ -270,7 +270,7 @@ func (c *compiler) compileLabel(attrs *d2graph.Attributes, f d2ir.Node) {
 		// TODO: Delete instead.
 		attrs.Label.Value = scalar.ScalarString()
 	case *d2ast.BlockString:
-		if scalar.ScalarString() == "" {
+		if strings.TrimSpace(scalar.ScalarString()) == "" {
 			c.errorf(f.LastPrimaryKey(), "block string cannot be empty")
 		}
 		attrs.Language = scalar.Tag
diff --git a/d2compiler/compile_test.go b/d2compiler/compile_test.go
index c7c6267da..3a73a9b08 100644
--- a/d2compiler/compile_test.go
+++ b/d2compiler/compile_test.go
@@ -611,9 +611,22 @@ x: {
 d2/testdata/d2compiler/TestCompile/md_block_string_err.d2:5:1: block string must be terminated with |`,
 		},
 		{
-			name:   "no_empty_block_strings",
+			name:   "no_empty_block_string",
 			text:   `Text: |md |`,
-			expErr: `d2/testdata/d2compiler/TestCompile/no_empty_block_strings.d2:1:1: block string cannot be empty`,
+			expErr: `d2/testdata/d2compiler/TestCompile/no_empty_block_string.d2:1:1: block string cannot be empty`,
+		},
+		{
+			name:   "no_white_spaces_only_block_string",
+			text:   `Text: |md      |`,
+			expErr: `d2/testdata/d2compiler/TestCompile/no_white_spaces_only_block_string.d2:1:1: block string cannot be empty`,
+		},
+		{
+			name: "no_new_lines_only_block_string",
+			text: `Text: |md
+
+
+|`,
+			expErr: `d2/testdata/d2compiler/TestCompile/no_new_lines_only_block_string.d2:1:1: block string cannot be empty`,
 		},
 		{
 			name: "underscore_edge_existing",
diff --git a/testdata/d2compiler/TestCompile/no_empty_block_string.exp.json b/testdata/d2compiler/TestCompile/no_empty_block_string.exp.json
new file mode 100644
index 000000000..bf0a8c3a8
--- /dev/null
+++ b/testdata/d2compiler/TestCompile/no_empty_block_string.exp.json
@@ -0,0 +1,12 @@
+{
+  "graph": null,
+  "err": {
+    "ioerr": null,
+    "errs": [
+      {
+        "range": "d2/testdata/d2compiler/TestCompile/no_empty_block_string.d2,0:0:0-0:11:11",
+        "errmsg": "d2/testdata/d2compiler/TestCompile/no_empty_block_string.d2:1:1: block string cannot be empty"
+      }
+    ]
+  }
+}
diff --git a/testdata/d2compiler/TestCompile/no_new_lines_only_block_string.exp.json b/testdata/d2compiler/TestCompile/no_new_lines_only_block_string.exp.json
new file mode 100644
index 000000000..2dff86029
--- /dev/null
+++ b/testdata/d2compiler/TestCompile/no_new_lines_only_block_string.exp.json
@@ -0,0 +1,12 @@
+{
+  "graph": null,
+  "err": {
+    "ioerr": null,
+    "errs": [
+      {
+        "range": "d2/testdata/d2compiler/TestCompile/no_new_lines_only_block_string.d2,0:0:0-3:1:13",
+        "errmsg": "d2/testdata/d2compiler/TestCompile/no_new_lines_only_block_string.d2:1:1: block string cannot be empty"
+      }
+    ]
+  }
+}
diff --git a/testdata/d2compiler/TestCompile/no_white_spaces_only_block_string.exp.json b/testdata/d2compiler/TestCompile/no_white_spaces_only_block_string.exp.json
new file mode 100644
index 000000000..ab68a6cc0
--- /dev/null
+++ b/testdata/d2compiler/TestCompile/no_white_spaces_only_block_string.exp.json
@@ -0,0 +1,12 @@
+{
+  "graph": null,
+  "err": {
+    "ioerr": null,
+    "errs": [
+      {
+        "range": "d2/testdata/d2compiler/TestCompile/no_white_spaces_only_block_string.d2,0:0:0-0:16:16",
+        "errmsg": "d2/testdata/d2compiler/TestCompile/no_white_spaces_only_block_string.d2:1:1: block string cannot be empty"
+      }
+    ]
+  }
+}