diff --git a/src/Classes/CalcsTab.lua b/src/Classes/CalcsTab.lua
index 094c7c155b..fe751b4674 100644
--- a/src/Classes/CalcsTab.lua
+++ b/src/Classes/CalcsTab.lua
@@ -473,7 +473,7 @@ end
 
 -- Estimate the offensive and defensive power of all unallocated nodes
 function CalcsTabClass:PowerBuilder()
-	--local timer_start = GetTime()
+	-- local timer_start = GetTime()
 	local useFullDPS = self.powerStat and self.powerStat.stat == "FullDPS"
 	local calcFunc, calcBase = self:GetMiscCalculator()
 	local cache = { }
@@ -494,11 +494,17 @@ function CalcsTabClass:PowerBuilder()
 	end
 	
 	local start = GetTime()
+	local nodeIndex = 0
+	local total = 0
+
 	for nodeId, node in pairs(self.build.spec.nodes) do
 		wipeTable(node.power)
 		if node.modKey ~= "" and not self.mainEnv.grantedPassives[nodeId] then
 			distanceMap[node.pathDist or 1000] = distanceMap[node.pathDist or 1000] or { }
 			distanceMap[node.pathDist or 1000][nodeId] = node
+			if not (self.nodePowerMaxDepth and self.nodePowerMaxDepth < node.pathDist) then
+				total = total + 1
+			end
 		end
 	end
 	for distance, nodes in pairs(distanceMap) do
@@ -506,6 +512,13 @@ function CalcsTabClass:PowerBuilder()
 	end
 	distanceMap = nil
 	table.sort(distanceList, function(a, b) return a[1] < b[1] end)
+	-- Count eligible cluster nodes
+	for _, node in pairs(self.build.spec.tree.clusterNodeMap) do
+		if not node.alloc and node.modKey ~= "" and not self.mainEnv.grantedPassives[node.id] then
+			total = total + 1
+		end
+	end
+
 	for _, data in ipairs(distanceList) do
 		local distance, nodes = data[1], data[2]
 		if self.nodePowerMaxDepth and self.nodePowerMaxDepth < distance then
@@ -559,7 +572,11 @@ function CalcsTabClass:PowerBuilder()
 					end
 				end
 			end
+			nodeIndex = nodeIndex + 1
 			if coroutine.running() and GetTime() - start > 100 then
+				if self.build.powerBuilderProgressCallback then
+					self.build.powerBuilderProgressCallback(m_floor(nodeIndex/total*100))
+				end
 				coroutine.yield()
 				start = GetTime()
 			end
@@ -581,15 +598,19 @@ function CalcsTabClass:PowerBuilder()
 			if self.powerStat and self.powerStat.stat and not self.powerStat.ignoreForNodes then
 				node.power.singleStat = self:CalculatePowerStat(self.powerStat, output, calcBase)
 			end
-		end
-		if coroutine.running() and GetTime() - start > 100 then
-			coroutine.yield()
-			start = GetTime()
+			nodeIndex = nodeIndex + 1
+			if coroutine.running() and GetTime() - start > 100 then
+				if self.build.powerBuilderProgressCallback then
+					self.build.powerBuilderProgressCallback(m_floor(nodeIndex/total*100))
+				end
+				coroutine.yield()
+				start = GetTime()
+			end
 		end
 	end
 	self.powerMax = newPowerMax
 	self.powerBuilderInitialized = true
-	--ConPrintf("Power Build time: %d ms", GetTime() - timer_start)
+	-- ConPrintf("Power Build time: %d ms", GetTime() - timer_start)
 end
 
 function CalcsTabClass:CalculatePowerStat(selection, original, modified)
diff --git a/src/Classes/TreeTab.lua b/src/Classes/TreeTab.lua
index c19edf0223..28bafbc548 100644
--- a/src/Classes/TreeTab.lua
+++ b/src/Classes/TreeTab.lua
@@ -278,10 +278,38 @@ local TreeTabClass = newClass("TreeTab", "ControlHost", function(self, build)
 		end
 	end)
 	self.controls.powerReportList.shown = false
+	-- Progress callback from the CalcsTab power builder coroutine
+	self.powerBuilderToastIndex = nil
+	self.lastProgressToastUpdate = 0
+	self.build.powerBuilderProgressCallback = function(percent)
+		local now = GetTime()
+		if now - self.lastProgressToastUpdate < 100 then
+			return
+		end
+
+		local message = percent and string.format("Building Tree... (%d%%)", percent) or "Building Tree..."
+
+		self.controls.powerReportList.label = message
+		self.lastProgressToastUpdate = now
+		if self.powerBuilderToastIndex then
+			if main.toastMessages[self.powerBuilderToastIndex] and main.toastMessages[self.powerBuilderToastIndex]:match("^Building Tree") then
+				main.toastMessages[self.powerBuilderToastIndex] = message
+			end
+		else
+			t_insert(main.toastMessages, message)
+			self.powerBuilderToastIndex = 1
+		end
+	end
+	-- Completion callback from the CalcsTab power builder coroutine
 	self.build.powerBuilderCallback = function()
 		local powerStat = self.build.calcsTab.powerStat or data.powerStatList[1]
 		local report = self:BuildPowerReportList(powerStat)
 		self.controls.powerReportList:SetReport(powerStat, report)
+		if self.powerBuilderToastIndex and main.toastMessages[self.powerBuilderToastIndex] and main.toastMessages[self.powerBuilderToastIndex]:match("^Building Tree") then
+			main.toastMode = "HIDING"
+			main.toastStart = GetTime()
+		end
+		self.powerBuilderToastIndex = nil
 	end
 
 	self.controls.specConvertText = new("LabelControl", { "BOTTOMLEFT", self.controls.specSelect, "TOPLEFT" }, { 0, -14, 0, 16 }, "^7This is an older tree version, which may not be fully compatible with the current game version.")