diff --git a/website/src/heatmap/index.js b/website/src/heatmap/index.js
index affe6d987..98a31766a 100644
--- a/website/src/heatmap/index.js
+++ b/website/src/heatmap/index.js
@@ -116,6 +116,7 @@ function loadRange() {
   }
 
   let cursor = 0;
+  let needsRebuild = false;
   const workers = Array.from({
     length: Math.min(MAX_PARALLEL_FETCHES, missing.length),
   }).map(async () => {
@@ -123,10 +124,17 @@ function loadRange() {
     while (index !== undefined) {
       const entry = missing[index];
       try {
-        const points = await option.points.fetch(entry.date, controller.signal);
+        const points = await option.points.fetch(
+          entry.date,
+          controller.signal,
+          (points) => {
+            if (isCurrentLoad(option, controller, generation)) {
+              setPoints(entry, points);
+            }
+          },
+        );
         if (isCurrentLoad(option, controller, generation)) {
-          pointsByDate.set(entry.date, points);
-          addDateToGrid(entry.dateIndex, points);
+          setPoints(entry, points);
         }
       } catch (error) {
         if (controller.signal.aborted) return;
@@ -147,7 +155,11 @@ function loadRange() {
   void Promise.all(workers).then(() => {
     if (isCurrentLoad(option, controller, generation)) {
       updateStatus(completed, currentDates.length, failed);
-      paint();
+      if (needsRebuild) {
+        rebuildGrid();
+      } else {
+        paint();
+      }
     }
   });
 
@@ -157,6 +169,21 @@ function loadRange() {
     cursor += 1;
     return index;
   }
+
+  /**
+   * @param {{ date: string, dateIndex: number }} entry
+   * @param {HeatmapPoints} points
+   */
+  function setPoints(entry, points) {
+    const previous = pointsByDate.get(entry.date);
+    if (previous && samePoints(previous, points)) return;
+    pointsByDate.set(entry.date, points);
+    if (previous) {
+      needsRebuild = true;
+    } else {
+      addDateToGrid(entry.dateIndex, points);
+    }
+  }
 }
 
 /**
@@ -209,6 +236,20 @@ function addDateToGrid(dateIndex, points) {
   if (dirtyCol !== undefined) schedulePaint(dirtyCol);
 }
 
+/**
+ * @param {HeatmapPoints} a
+ * @param {HeatmapPoints} b
+ */
+function samePoints(a, b) {
+  if (a === b) return true;
+  if (a.kind !== b.kind || a.values !== b.values) return false;
+  if (a.kind === "implicit" && b.kind === "implicit") {
+    return a.yStart === b.yStart && a.yStep === b.yStep;
+  }
+  if (a.kind === "explicit" && b.kind === "explicit") return a.y === b.y;
+  return false;
+}
+
 /** @param {number} col */
 function schedulePaint(col) {
   dirtyCols.add(col);
diff --git a/website/src/heatmap/oracle.js b/website/src/heatmap/oracle.js
index b8391a7cb..6aca8a52d 100644
--- a/website/src/heatmap/oracle.js
+++ b/website/src/heatmap/oracle.js
@@ -9,6 +9,7 @@ import { defaultTooltip } from "./tooltip.js";
 const BINS = 2400;
 const MIN_LOG = -8;
 const BINS_PER_DECADE = 200;
+const MAX_LOG = MIN_LOG + (BINS - 1) / BINS_PER_DECADE;
 
 export const oracleRawHeatmapOption = createOracleHeatmapOption("raw", "Raw");
 export const oracleEmaHeatmapOption = createOracleHeatmapOption("ema", "EMA");
@@ -24,7 +25,8 @@ function createOracleHeatmapOption(mode, name) {
     name,
     title: `Oracle ${name} Histogram`,
     points: {
-      fetch: (date, signal) => fetchOraclePoints(mode, date, signal),
+      fetch: (date, signal, onPoints) =>
+        fetchOraclePoints(mode, date, signal, onPoints),
     },
     grid: createAverageGrid({
       yStart: MIN_LOG,
@@ -40,40 +42,44 @@ function createOracleHeatmapOption(mode, name) {
  * @param {"raw" | "ema"} mode
  * @param {string} date
  * @param {AbortSignal} signal
+ * @param {(points: HeatmapPoints) => void} [onPoints]
  * @returns {Promise<HeatmapPoints>}
  */
-async function fetchOraclePoints(mode, date, signal) {
-  const values = await firstAvailable((onValue) =>
-    mode === "raw"
-      ? brk.getOracleHistogramRaw(date, { signal, onValue })
-      : brk.getOracleHistogramEma(date, { signal, onValue }),
+async function fetchOraclePoints(mode, date, signal, onPoints) {
+  const values = await fetchOracleValues(
+    mode,
+    date,
+    signal,
+    onPoints ? (values) => onPoints(toOraclePoints(values)) : undefined,
   );
 
-  return {
-    kind: "implicit",
-    yStart: MIN_LOG,
-    yStep: 1 / BINS_PER_DECADE,
-    values,
-  };
+  return toOraclePoints(values);
 }
 
 /**
- * @param {(onValue: (value: number[]) => void) => Promise<number[]>} fetch
+ * @param {"raw" | "ema"} mode
+ * @param {string} date
+ * @param {AbortSignal} signal
+ * @param {(values: number[]) => void} [onValue]
  * @returns {Promise<number[]>}
  */
-function firstAvailable(fetch) {
-  return new Promise((resolve, reject) => {
-    let settled = false;
-
-    /** @param {number[]} value */
-    const resolveOnce = (value) => {
-      if (settled) return;
-      settled = true;
-      resolve(value);
-    };
-
-    fetch(resolveOnce).then(resolveOnce, (error) => {
-      if (!settled) reject(error);
-    });
-  });
+function fetchOracleValues(mode, date, signal, onValue) {
+  return (
+    mode === "raw"
+      ? brk.getOracleHistogramRaw(date, { signal, onValue })
+      : brk.getOracleHistogramEma(date, { signal, onValue })
+  );
+}
+
+/**
+ * @param {number[]} values
+ * @returns {HeatmapPoints}
+ */
+function toOraclePoints(values) {
+  return {
+    kind: "implicit",
+    yStart: MAX_LOG,
+    yStep: -1 / BINS_PER_DECADE,
+    values,
+  };
 }
diff --git a/website/src/heatmap/types.js b/website/src/heatmap/types.js
index 5a84cf0ee..4cc6f0254 100644
--- a/website/src/heatmap/types.js
+++ b/website/src/heatmap/types.js
@@ -13,7 +13,7 @@
  * @typedef {HeatmapImplicitPoints | HeatmapExplicitPoints} HeatmapPoints
  *
  * @typedef {Object} HeatmapPointSource
- * @property {(date: string, signal: AbortSignal) => Promise<HeatmapPoints>} fetch
+ * @property {(date: string, signal: AbortSignal, onPoints?: (points: HeatmapPoints) => void) => Promise<HeatmapPoints>} fetch
  *
  * @typedef {Object} HeatmapRange
  * @property {number} start