diff --git a/grafana/dashboard.json b/grafana/dashboard.json
index f1e76f72..4297d8c0 100644
--- a/grafana/dashboard.json
+++ b/grafana/dashboard.json
@@ -408,6 +408,88 @@
       "title": "Pub/sub backlog",
       "type": "timeseries"
     },
+    {
+      "datasource": {
+        "type": "prometheus",
+        "uid": "f6b18033-5918-4e05-a1ca-4cb30343b129"
+      },
+      "fieldConfig": {
+        "defaults": {
+          "custom": {
+            "hideFrom": {
+              "legend": false,
+              "tooltip": false,
+              "viz": false
+            },
+            "scaleDistribution": {
+              "type": "linear"
+            }
+          }
+        },
+        "overrides": []
+      },
+      "gridPos": {
+        "h": 6,
+        "w": 12,
+        "x": 0,
+        "y": 17
+      },
+      "id": 9,
+      "options": {
+        "calculate": false,
+        "cellGap": 1,
+        "color": {
+          "exponent": 0.5,
+          "fill": "dark-orange",
+          "mode": "scheme",
+          "reverse": false,
+          "scale": "exponential",
+          "scheme": "Greys",
+          "steps": 64
+        },
+        "exemplars": {
+          "color": "rgba(255,0,255,0.7)"
+        },
+        "filterValues": {
+          "le": 1e-9
+        },
+        "legend": {
+          "show": true
+        },
+        "rowsFrame": {
+          "layout": "auto"
+        },
+        "tooltip": {
+          "show": true,
+          "yHistogram": false
+        },
+        "yAxis": {
+          "axisPlacement": "left",
+          "reverse": false
+        }
+      },
+      "pluginVersion": "10.0.0",
+      "targets": [
+        {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "f6b18033-5918-4e05-a1ca-4cb30343b129"
+          },
+          "editorMode": "builder",
+          "exemplar": false,
+          "expr": "rate(chunk_size_bucket[$__rate_interval])",
+          "format": "heatmap",
+          "hide": false,
+          "instant": false,
+          "interval": "",
+          "legendFormat": "{{le}}",
+          "range": true,
+          "refId": "A"
+        }
+      ],
+      "title": "Chunk size",
+      "type": "heatmap"
+    },
     {
       "datasource": {
         "type": "prometheus",
@@ -417,7 +499,7 @@
         "h": 11,
         "w": 24,
         "x": 0,
-        "y": 17
+        "y": 23
       },
       "id": 8,
       "targets": [
@@ -438,7 +520,7 @@
       "type": "nodeGraph"
     }
   ],
-  "refresh": "5m",
+  "refresh": "5s",
   "schemaVersion": 38,
   "style": "dark",
   "tags": [],
@@ -446,13 +528,13 @@
     "list": []
   },
   "time": {
-    "from": "now-30m",
+    "from": "now-15m",
     "to": "now"
   },
   "timepicker": {},
   "timezone": "",
   "title": "Overview",
   "uid": "b5c8abf8-fe79-496b-b028-10bde917d1f0",
-  "version": 3,
+  "version": 2,
   "weekStart": ""
 }
diff --git a/trustgraph/chunking/recursive/chunker.py b/trustgraph/chunking/recursive/chunker.py
index d38b580a..fe1a0cee 100755
--- a/trustgraph/chunking/recursive/chunker.py
+++ b/trustgraph/chunking/recursive/chunker.py
@@ -5,7 +5,7 @@ as text as separate output objects.
 """
 
 from langchain_text_splitters import RecursiveCharacterTextSplitter
-
+from prometheus_client import Histogram
 
 from ... schema import TextDocument, Chunk, Source
 from ... schema import text_ingest_queue, chunk_ingest_queue
@@ -38,6 +38,13 @@ class Processor(ConsumerProducer):
             }
         )
 
+        if not hasattr(__class__, "chunk_metric"):
+            __class__.chunk_metric = Histogram(
+                'chunk_size', 'Chunk size',
+                buckets=[100, 160, 250, 400, 650, 1000, 1600,
+                         2500, 4000, 6400, 10000, 16000]
+            )
+
         self.text_splitter = RecursiveCharacterTextSplitter(
             chunk_size=chunk_size,
             chunk_overlap=chunk_overlap,
@@ -67,6 +74,8 @@ class Processor(ConsumerProducer):
                 chunk=chunk.page_content.encode("utf-8"),
             )
 
+            __class__.chunk_metric.observe(len(chunk.page_content))
+
             self.send(r)
 
         print("Done.", flush=True)
diff --git a/trustgraph/chunking/token/chunker.py b/trustgraph/chunking/token/chunker.py
index 78afeff3..c152b0fd 100755
--- a/trustgraph/chunking/token/chunker.py
+++ b/trustgraph/chunking/token/chunker.py
@@ -5,6 +5,7 @@ as text as separate output objects.
 """
 
 from langchain_text_splitters import TokenTextSplitter
+from prometheus_client import Histogram
 
 from ... schema import TextDocument, Chunk, Source
 from ... schema import text_ingest_queue, chunk_ingest_queue
@@ -37,6 +38,13 @@ class Processor(ConsumerProducer):
             }
         )
 
+        if not hasattr(__class__, "chunk_metric"):
+            __class__.chunk_metric = Histogram(
+                'chunk_size', 'Chunk size',
+                buckets=[100, 160, 250, 400, 650, 1000, 1600,
+                         2500, 4000, 6400, 10000, 16000]
+            )
+
         self.text_splitter = TokenTextSplitter(
             encoding_name="cl100k_base",
             chunk_size=chunk_size,
@@ -65,6 +73,8 @@ class Processor(ConsumerProducer):
                 chunk=chunk.page_content.encode("utf-8"),
             )
 
+            __class__.chunk_metric.observe(len(chunk.page_content))
+
             self.send(r)
 
         print("Done.", flush=True)