diff --git a/pybigtools/src/lib.rs b/pybigtools/src/lib.rs
index ac7ade8..b0c30d5 100644
--- a/pybigtools/src/lib.rs
+++ b/pybigtools/src/lib.rs
@@ -285,7 +285,7 @@ fn intervals_to_array<R: BBIFileRead>(
                 .convert_err()?;
             to_array(start, end, iter, missing, array.as_array_mut()).convert_err()?;
 
-            (end - start) as f64
+            1.0
         }
     };
 
@@ -301,7 +301,7 @@ fn intervals_to_array<R: BBIFileRead>(
                 array[i] = oob;
             }
         }
-        if end >= length {
+        if end > length {
             let interval_start = (length as i32) - start;
             let interval_end = end - start;
             let bin_start = ((interval_start as f64) / bin_size) as usize;
@@ -421,7 +421,7 @@ fn entries_to_array<R: BBIFileRead>(
                 .convert_err()?;
             to_entry_array(start, end, iter, missing, array.as_array_mut()).convert_err()?;
 
-            (end - start) as f64
+            1.0
         }
     };
 
@@ -437,7 +437,7 @@ fn entries_to_array<R: BBIFileRead>(
                 array[i] = oob;
             }
         }
-        if end >= length {
+        if end > length {
             let interval_start = (length as i32) - start;
             let interval_end = end - start;
             let bin_start = ((interval_start as f64) / bin_size) as usize;
diff --git a/pybigtools/tests/test_api.py b/pybigtools/tests/test_api.py
index 189536f..4f7c933 100644
--- a/pybigtools/tests/test_api.py
+++ b/pybigtools/tests/test_api.py
@@ -244,6 +244,15 @@ def test_zoom_records(bw, bb):
     assert pytest.raises(KeyError, bw.zoom_records, 10, "chr11")
     assert pytest.raises(KeyError, bb.zoom_records, 3911, "chr11")
 
+def test_values_no_end(bw, bb):
+    # (chrom, None, None) => all values on chrom
+    assert len(bw.values("chr17")) == 83_257_441
+    assert len(bb.values("chr21")) == 48_129_895
+    # (chrom, start, None) => all values from (start, <chrom_end>)
+    assert len(bw.values("chr17", 0)) == 83_257_441
+    assert len(bw.values("chr17", 10)) == 83_257_441 - 10
+    assert len(bb.values("chr21", 0)) == 48_129_895
+    assert len(bb.values("chr21", 10)) == 48_129_895 - 10
 
 def test_values(bw, bb):
     assert len(bw.values("chr17", 100_000, 110_000)) == 10_000