diff --git a/README.md b/README.md
index c14a799..02dff26 100644
--- a/README.md
+++ b/README.md
@@ -23,6 +23,22 @@ sudo pip install .
 Usage
 -----
 ~~~
+Usage: dinglehopper [OPTIONS] GT OCR [REPORT_PREFIX]
+
+  Compare the PAGE/ALTO/text document GT against the document OCR.
+
+  The files GT and OCR are usually a ground truth document and the result of
+  an OCR software, but you may use dinglehopper to compare two OCR results.
+  In that case, use --no-metrics to disable the then meaningless metrics and
+  also change the color scheme from green/red to blue.
+
+Options:
+  --metrics / --no-metrics  Enable/disable metrics and green/red
+  --help                    Show this message and exit.
+~~~
+
+For example:
+~~~
 dinglehopper some-document.gt.page.xml some-document.ocr.alto.xml
 ~~~
 This generates `report.html` and `report.json`.
diff --git a/qurator/dinglehopper/cli.py b/qurator/dinglehopper/cli.py
index 08a36bb..e62d8b6 100644
--- a/qurator/dinglehopper/cli.py
+++ b/qurator/dinglehopper/cli.py
@@ -44,7 +44,7 @@ def gen_diff_report(gt_things, ocr_things, css_prefix, joiner, none, align):
         '''.format(gtx, ocrx)
 
 
-def process(gt, ocr, report_prefix):
+def process(gt, ocr, report_prefix, metrics):
     """Check OCR result against GT.
 
     The @click decorators change the signature of the decorated functions, so we keep this undecorated version and use
@@ -91,7 +91,8 @@ def process(gt, ocr, report_prefix):
             cer=cer, n_characters=n_characters,
             wer=wer, n_words=n_words,
             char_diff_report=char_diff_report,
-            word_diff_report=word_diff_report
+            word_diff_report=word_diff_report,
+            metrics=metrics,
         ).dump(out_fn)
 
 
@@ -99,8 +100,17 @@ def process(gt, ocr, report_prefix):
 @click.argument('gt', type=click.Path(exists=True))
 @click.argument('ocr', type=click.Path(exists=True))
 @click.argument('report_prefix', type=click.Path(), default='report')
-def main(gt, ocr, report_prefix):
-    process(gt, ocr, report_prefix)
+@click.option('--metrics/--no-metrics', default=True, help='Enable/disable metrics and green/red')
+def main(gt, ocr, report_prefix, metrics):
+    """
+    Compare the PAGE/ALTO/text document GT against the document OCR.
+
+    The files GT and OCR are usually a ground truth document and the result of
+    an OCR software, but you may use dinglehopper to compare two OCR results. In
+    that case, use --no-metrics to disable the then meaningless metrics and also
+    change the color scheme from green/red to blue.
+    """
+    process(gt, ocr, report_prefix, metrics)
 
 
 if __name__ == '__main__':
diff --git a/qurator/dinglehopper/templates/report.html.j2 b/qurator/dinglehopper/templates/report.html.j2
index 80ffae3..0c2f464 100644
--- a/qurator/dinglehopper/templates/report.html.j2
+++ b/qurator/dinglehopper/templates/report.html.j2
@@ -6,12 +6,18 @@
 
     <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
     <style type="text/css">
+    {% if metrics %}
     .gt .diff {
         color: green;
     }
     .ocr .diff {
         color: red;
     }
+    {% else %}
+    .gt .diff, .ocr .diff {
+        color: blue;
+    }
+    {% endif %}
     .ellipsis {
         opacity: 0.5;
         font-style: italic;
@@ -32,9 +38,11 @@
 {{ ocr }}
 
 
+{% if metrics %}
 <h2>Metrics</h2>
 <p>CER: {{ cer|round(4) }}</p>
 <p>WER: {{ wer|round(4) }}</p>
+{% endif %}
 
 <h2>Character differences</h2>
 {{ char_diff_report }}