diff --git a/.prettierignore b/.prettierignore
deleted file mode 100644
index e7faf7a6..00000000
--- a/.prettierignore
+++ /dev/null
@@ -1,2 +0,0 @@
-optuna_dashboard/ts/components/PlotlyDarkMode.ts
-standalone_app/src/PlotlyDarkMode.ts
diff --git a/.prettierrc b/.prettierrc
deleted file mode 100644
index 24ae9a99..00000000
--- a/.prettierrc
+++ /dev/null
@@ -1,4 +0,0 @@
-trailingComma: "es5"
-tabWidth: 2
-semi: false
-singleQuote: false
diff --git a/biome.json b/biome.json
new file mode 100644
index 00000000..740e9600
--- /dev/null
+++ b/biome.json
@@ -0,0 +1,28 @@
+{
+	"$schema": "https://biomejs.dev/schemas/1.5.3/schema.json",
+	"files": {
+		"include": [
+			"optuna_dashboard/ts/**/*.ts",
+			"optuna_dashboard/ts/**/*.tsx",
+			"typescript_tests/**/*.ts",
+			"typescript_tests/**/*.tsx",
+			"standalone_app/src/**/*.ts",
+			"standalone_app/src/**/*.tsx",
+			"vscode/src/**/*.ts",
+			"vscode/src/**/*.tsx"
+		],
+		"ignore": [
+			"optuna_dashboard/ts/components/PlotlyDarkMode.ts",
+			"standalone_app/src/PlotlyDarkMode.ts"
+		]
+	},
+	"javascript": {
+		"formatter": {
+			"trailingComma": "es5",
+			"indentWidth": 2,
+			"indentStyle": "space",
+			"semicolons": "asNeeded",
+			"quoteStyle": "double"
+		}
+	}
+}
diff --git a/optuna_dashboard/ts/components/Artifact/DeleteArtifactDialog.tsx b/optuna_dashboard/ts/components/Artifact/DeleteArtifactDialog.tsx
index 2055ea4c..4c2f16d1 100644
--- a/optuna_dashboard/ts/components/Artifact/DeleteArtifactDialog.tsx
+++ b/optuna_dashboard/ts/components/Artifact/DeleteArtifactDialog.tsx
@@ -11,7 +11,7 @@ import { actionCreator } from "../../action"
 
 export const useDeleteTrialArtifactDialog = (): [
   (studyId: number, trialId: number, artifact: Artifact) => void,
-  () => ReactNode
+  () => ReactNode,
 ] => {
   const action = actionCreator()
 
@@ -58,7 +58,7 @@ export const useDeleteTrialArtifactDialog = (): [
 
 export const useDeleteStudyArtifactDialog = (): [
   (studyId: number, artifact: Artifact) => void,
-  () => ReactNode
+  () => ReactNode,
 ] => {
   const action = actionCreator()
 
diff --git a/optuna_dashboard/ts/components/Artifact/ThreejsArtifactViewer.tsx b/optuna_dashboard/ts/components/Artifact/ThreejsArtifactViewer.tsx
index 8e574680..7787e8a4 100644
--- a/optuna_dashboard/ts/components/Artifact/ThreejsArtifactViewer.tsx
+++ b/optuna_dashboard/ts/components/Artifact/ThreejsArtifactViewer.tsx
@@ -124,7 +124,7 @@ export const ThreejsArtifactViewer: React.FC<ThreejsArtifactViewerProps> = (
 
 export const useThreejsArtifactModal = (): [
   (path: string, artifact: Artifact) => void,
-  () => ReactNode
+  () => ReactNode,
 ] => {
   const [open, setOpen] = useState(false)
   const [target, setTarget] = useState<[string, Artifact | null]>(["", null])
diff --git a/optuna_dashboard/ts/components/Artifact/WaveSurferArtifactViewer.tsx b/optuna_dashboard/ts/components/Artifact/WaveSurferArtifactViewer.tsx
index 74177602..96713e69 100644
--- a/optuna_dashboard/ts/components/Artifact/WaveSurferArtifactViewer.tsx
+++ b/optuna_dashboard/ts/components/Artifact/WaveSurferArtifactViewer.tsx
@@ -34,39 +34,38 @@ const useWavesurfer = (
 }
 
 // Create a React component of wavesurfer.
-export const WaveSurferArtifactViewer: React.FC<
-  WaveSurferArtifactViewerProps
-> = (props) => {
-  const containerRef = useRef<HTMLDivElement>(null!)
-  const [isPlaying, setIsPlaying] = useState(false)
-  const wavesurfer = useWavesurfer(containerRef, props)
+export const WaveSurferArtifactViewer: React.FC<WaveSurferArtifactViewerProps> =
+  (props) => {
+    const containerRef = useRef<HTMLDivElement>(null!)
+    const [isPlaying, setIsPlaying] = useState(false)
+    const wavesurfer = useWavesurfer(containerRef, props)
 
-  const onPlayClick = useCallback(() => {
-    if (!wavesurfer) return
-    wavesurfer.isPlaying() ? wavesurfer.pause() : wavesurfer.play()
-  }, [wavesurfer])
+    const onPlayClick = useCallback(() => {
+      if (!wavesurfer) return
+      wavesurfer.isPlaying() ? wavesurfer.pause() : wavesurfer.play()
+    }, [wavesurfer])
 
-  useEffect(() => {
-    if (!wavesurfer) return
+    useEffect(() => {
+      if (!wavesurfer) return
 
-    setIsPlaying(false)
+      setIsPlaying(false)
 
-    const subscriptions = [
-      wavesurfer.on("play", () => setIsPlaying(true)),
-      wavesurfer.on("pause", () => setIsPlaying(false)),
-    ]
+      const subscriptions = [
+        wavesurfer.on("play", () => setIsPlaying(true)),
+        wavesurfer.on("pause", () => setIsPlaying(false)),
+      ]
 
-    return () => {
-      subscriptions.forEach((unsub) => unsub())
-    }
-  }, [wavesurfer])
+      return () => {
+        subscriptions.forEach((unsub) => unsub())
+      }
+    }, [wavesurfer])
 
-  return (
-    <Box style={{ width: "100%", display: "flex", flexDirection: "column" }}>
-      <div ref={containerRef} style={{ minHeight: "120px", width: "100%" }} />
-      <button onClick={onPlayClick} style={{ marginTop: "1em" }}>
-        {isPlaying ? "Pause" : "Play"}
-      </button>
-    </Box>
-  )
-}
+    return (
+      <Box style={{ width: "100%", display: "flex", flexDirection: "column" }}>
+        <div ref={containerRef} style={{ minHeight: "120px", width: "100%" }} />
+        <button onClick={onPlayClick} style={{ marginTop: "1em" }}>
+          {isPlaying ? "Pause" : "Play"}
+        </button>
+      </Box>
+    )
+  }
diff --git a/optuna_dashboard/ts/components/DataGrid.tsx b/optuna_dashboard/ts/components/DataGrid.tsx
index 22693a5b..2aaba509 100644
--- a/optuna_dashboard/ts/components/DataGrid.tsx
+++ b/optuna_dashboard/ts/components/DataGrid.tsx
@@ -71,8 +71,8 @@ function DataGrid<T>(props: {
   initialRowsPerPage = initialRowsPerPage // use first element as default
     ? initialRowsPerPage
     : isNumber(rowsPerPageOption[0])
-    ? rowsPerPageOption[0]
-    : rowsPerPageOption[0].value
+      ? rowsPerPageOption[0]
+      : rowsPerPageOption[0].value
   const [rowsPerPage, setRowsPerPage] = React.useState(initialRowsPerPage)
 
   const handleChangePage = (event: unknown, newPage: number) => {
@@ -321,8 +321,8 @@ function DataGridHeaderColumn<T>(props: {
                       filter === null
                         ? filterChoices.filter((v) => v !== choice) // By default, every choice is ticked, so the chosen option will be unticked.
                         : filter.values.some((v) => v === choice)
-                        ? filter.values.filter((v) => v !== choice)
-                        : [...filter.values, choice]
+                          ? filter.values.filter((v) => v !== choice)
+                          : [...filter.values, choice]
                     onFilterChange(newTickedValues)
                   }}
                 >
diff --git a/optuna_dashboard/ts/components/DeleteStudyDialog.tsx b/optuna_dashboard/ts/components/DeleteStudyDialog.tsx
index c7d7a135..73940b2a 100644
--- a/optuna_dashboard/ts/components/DeleteStudyDialog.tsx
+++ b/optuna_dashboard/ts/components/DeleteStudyDialog.tsx
@@ -11,7 +11,7 @@ import { actionCreator } from "../action"
 
 export const useDeleteStudyDialog = (): [
   (studyId: number) => void,
-  () => ReactNode
+  () => ReactNode,
 ] => {
   const action = actionCreator()
 
diff --git a/optuna_dashboard/ts/components/GraphHistory.tsx b/optuna_dashboard/ts/components/GraphHistory.tsx
index 0afcb555..4bd2fd76 100644
--- a/optuna_dashboard/ts/components/GraphHistory.tsx
+++ b/optuna_dashboard/ts/components/GraphHistory.tsx
@@ -251,8 +251,8 @@ const plotHistory = (
     return xAxis === "number"
       ? trial.number
       : xAxis === "datetime_start"
-      ? trial.datetime_start ?? new Date()
-      : trial.datetime_complete ?? new Date()
+        ? trial.datetime_start ?? new Date()
+        : trial.datetime_complete ?? new Date()
   }
 
   const plotData: Partial<plotly.PlotData>[] = []
diff --git a/optuna_dashboard/ts/components/GraphIntermediateValues.tsx b/optuna_dashboard/ts/components/GraphIntermediateValues.tsx
index a06832d9..d0a3c075 100644
--- a/optuna_dashboard/ts/components/GraphIntermediateValues.tsx
+++ b/optuna_dashboard/ts/components/GraphIntermediateValues.tsx
@@ -95,8 +95,8 @@ const plotIntermediateValue = (
         trial.state === "Running"
           ? "(running)"
           : !isFeasible
-          ? "(infeasible)"
-          : ""
+            ? "(infeasible)"
+            : ""
       }`,
       ...(!isFeasible && { line: { color: "#CCCCCC" } }),
     }
diff --git a/optuna_dashboard/ts/components/GraphParetoFront.tsx b/optuna_dashboard/ts/components/GraphParetoFront.tsx
index f2b11145..ec8faef0 100644
--- a/optuna_dashboard/ts/components/GraphParetoFront.tsx
+++ b/optuna_dashboard/ts/components/GraphParetoFront.tsx
@@ -207,12 +207,12 @@ const getIsDominated2D = (normalizedValues: number[][]) => {
       a[0] > b[0]
         ? 1
         : a[0] < b[0]
-        ? -1
-        : a[1] > b[1]
-        ? 1
-        : a[1] < b[1]
-        ? -1
-        : 0
+          ? -1
+          : a[1] > b[1]
+            ? 1
+            : a[1] < b[1]
+              ? -1
+              : 0
     )
   let maxValueSeen0 = sorted[0][0]
   let minValueSeen1 = sorted[0][1]
diff --git a/optuna_dashboard/ts/components/GraphRank.tsx b/optuna_dashboard/ts/components/GraphRank.tsx
index ab25afeb..d1ce9d19 100644
--- a/optuna_dashboard/ts/components/GraphRank.tsx
+++ b/optuna_dashboard/ts/components/GraphRank.tsx
@@ -190,8 +190,8 @@ const getRankPlotInfo = (
     return typeof value === "number"
       ? value
       : value.includes("-")
-      ? -Infinity
-      : Infinity
+        ? -Infinity
+        : Infinity
   }
   filteredTrials.forEach((trial, i) => {
     const xValue = xAxis.values[i]
diff --git a/optuna_dashboard/ts/components/TrialFormWidgets.tsx b/optuna_dashboard/ts/components/TrialFormWidgets.tsx
index f727ac80..36bea2a7 100644
--- a/optuna_dashboard/ts/components/TrialFormWidgets.tsx
+++ b/optuna_dashboard/ts/components/TrialFormWidgets.tsx
@@ -42,8 +42,8 @@ export const TrialFormWidgets: FC<{
     formWidgets.output_type === "user_attr"
       ? "Set User Attributes Form"
       : directions.length > 1
-      ? "Set Objective Values Form"
-      : "Set Objective Value Form"
+        ? "Set Objective Values Form"
+        : "Set Objective Value Form"
   const widgetNames = formWidgets.widgets.map((widget, i) => {
     if (formWidgets.output_type === "objective") {
       if (objectiveNames.at(i) !== undefined) {
diff --git a/optuna_dashboard/ts/graphUtil.ts b/optuna_dashboard/ts/graphUtil.ts
index 35a9002b..2bed664e 100644
--- a/optuna_dashboard/ts/graphUtil.ts
+++ b/optuna_dashboard/ts/graphUtil.ts
@@ -47,8 +47,8 @@ const getAxisInfoForCategoricalParams = (
       a.toLowerCase() < b.toLowerCase()
         ? -1
         : a.toLowerCase() > b.toLowerCase()
-        ? 1
-        : 0
+          ? 1
+          : 0
     )
   return {
     name: paramName,
diff --git a/package-lock.json b/package-lock.json
index 1b432956..f6a8bdc3 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -38,6 +38,7 @@
       "devDependencies": {
         "@babel/core": "^7.23.9",
         "@babel/preset-env": "^7.23.9",
+        "@biomejs/biome": "1.5.3",
         "@testing-library/react": "^14.1.2",
         "@types/jest": "^29.5.11",
         "@types/plotly.js": "^2.12.32",
@@ -53,7 +54,6 @@
         "jest": "^29.7.0",
         "jest-canvas-mock": "^2.5.2",
         "jest-environment-jsdom": "^29.7.0",
-        "prettier": "^2.5.1",
         "style-loader": "^3.3.4",
         "ts-jest": "^29.1.2",
         "ts-loader": "^9.5.1",
@@ -1818,6 +1818,161 @@
       "integrity": "sha512-0hYQ8SB4Db5zvZB4axdMHGwEaQjkZzFjQiN9LVYvIFB2nSUHW9tYpxWriPrWDASIxiaXax83REcLxuSdnGPZtw==",
       "dev": true
     },
+    "node_modules/@biomejs/biome": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/biome/-/biome-1.5.3.tgz",
+      "integrity": "sha512-yvZCa/g3akwTaAQ7PCwPWDCkZs3Qa5ONg/fgOUT9e6wAWsPftCjLQFPXBeGxPK30yZSSpgEmRCfpGTmVbUjGgg==",
+      "dev": true,
+      "hasInstallScript": true,
+      "bin": {
+        "biome": "bin/biome"
+      },
+      "engines": {
+        "node": ">=14.*"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/biome"
+      },
+      "optionalDependencies": {
+        "@biomejs/cli-darwin-arm64": "1.5.3",
+        "@biomejs/cli-darwin-x64": "1.5.3",
+        "@biomejs/cli-linux-arm64": "1.5.3",
+        "@biomejs/cli-linux-arm64-musl": "1.5.3",
+        "@biomejs/cli-linux-x64": "1.5.3",
+        "@biomejs/cli-linux-x64-musl": "1.5.3",
+        "@biomejs/cli-win32-arm64": "1.5.3",
+        "@biomejs/cli-win32-x64": "1.5.3"
+      }
+    },
+    "node_modules/@biomejs/cli-darwin-arm64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-darwin-arm64/-/cli-darwin-arm64-1.5.3.tgz",
+      "integrity": "sha512-ImU7mh1HghEDyqNmxEZBoMPr8SxekkZuYcs+gynKlNW+TALQs7swkERiBLkG9NR0K1B3/2uVzlvYowXrmlW8hw==",
+      "cpu": [
+        "arm64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "darwin"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
+    "node_modules/@biomejs/cli-darwin-x64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-darwin-x64/-/cli-darwin-x64-1.5.3.tgz",
+      "integrity": "sha512-vCdASqYnlpq/swErH7FD6nrFz0czFtK4k/iLgj0/+VmZVjineFPgevOb+Sr9vz0tk0GfdQO60bSpI74zU8M9Dw==",
+      "cpu": [
+        "x64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "darwin"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
+    "node_modules/@biomejs/cli-linux-arm64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-arm64/-/cli-linux-arm64-1.5.3.tgz",
+      "integrity": "sha512-cupBQv0sNF1OKqBfx7EDWMSsKwRrBUZfjXawT4s6hKV6ALq7p0QzWlxr/sDmbKMLOaLQtw2Qgu/77N9rm+f9Rg==",
+      "cpu": [
+        "arm64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "linux"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
+    "node_modules/@biomejs/cli-linux-arm64-musl": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-arm64-musl/-/cli-linux-arm64-musl-1.5.3.tgz",
+      "integrity": "sha512-DYuMizUYUBYfS0IHGjDrOP1RGipqWfMGEvNEJ398zdtmCKLXaUvTimiox5dvx4X15mBK5M2m8wgWUgOP1giUpQ==",
+      "cpu": [
+        "arm64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "linux"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
+    "node_modules/@biomejs/cli-linux-x64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-x64/-/cli-linux-x64-1.5.3.tgz",
+      "integrity": "sha512-YQrSArQvcv4FYsk7Q91Yv4uuu5F8hJyORVcv3zsjCLGkjIjx2RhjYLpTL733SNL7v33GmOlZY0eFR1ko38tuUw==",
+      "cpu": [
+        "x64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "linux"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
+    "node_modules/@biomejs/cli-linux-x64-musl": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-x64-musl/-/cli-linux-x64-musl-1.5.3.tgz",
+      "integrity": "sha512-UUHiAnlDqr2Y/LpvshBFhUYMWkl2/Jn+bi3U6jKuav0qWbbBKU/ByHgR4+NBxpKBYoCtWxhnmatfH1bpPIuZMw==",
+      "cpu": [
+        "x64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "linux"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
+    "node_modules/@biomejs/cli-win32-arm64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-win32-arm64/-/cli-win32-arm64-1.5.3.tgz",
+      "integrity": "sha512-HxatYH7vf/kX9nrD+pDYuV2GI9GV8EFo6cfKkahAecTuZLPxryHx1WEfJthp5eNsE0+09STGkKIKjirP0ufaZA==",
+      "cpu": [
+        "arm64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "win32"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
+    "node_modules/@biomejs/cli-win32-x64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-win32-x64/-/cli-win32-x64-1.5.3.tgz",
+      "integrity": "sha512-fMvbSouZEASU7mZH8SIJSANDm5OqsjgtVXlbUqxwed6BP7uuHRSs396Aqwh2+VoW8fwTpp6ybIUoC9FrzB0kyA==",
+      "cpu": [
+        "x64"
+      ],
+      "dev": true,
+      "optional": true,
+      "os": [
+        "win32"
+      ],
+      "engines": {
+        "node": ">=14.*"
+      }
+    },
     "node_modules/@discoveryjs/json-ext": {
       "version": "0.5.7",
       "resolved": "https://registry.npmjs.org/@discoveryjs/json-ext/-/json-ext-0.5.7.tgz",
@@ -12830,21 +12985,6 @@
         "node": ">= 0.8.0"
       }
     },
-    "node_modules/prettier": {
-      "version": "2.8.8",
-      "resolved": "https://registry.npmjs.org/prettier/-/prettier-2.8.8.tgz",
-      "integrity": "sha512-tdN8qQGvNjw4CHbY+XXk0JgCXn9QiF21a55rBe5LJAU+kDyC4WQn4+awm2Xfk2lQMk5fKup9XgzTZtGkjBdP9Q==",
-      "dev": true,
-      "bin": {
-        "prettier": "bin-prettier.js"
-      },
-      "engines": {
-        "node": ">=10.13.0"
-      },
-      "funding": {
-        "url": "https://github.com/prettier/prettier?sponsor=1"
-      }
-    },
     "node_modules/pretty-format": {
       "version": "27.5.1",
       "resolved": "https://registry.npmjs.org/pretty-format/-/pretty-format-27.5.1.tgz",
@@ -16840,6 +16980,78 @@
       "integrity": "sha512-0hYQ8SB4Db5zvZB4axdMHGwEaQjkZzFjQiN9LVYvIFB2nSUHW9tYpxWriPrWDASIxiaXax83REcLxuSdnGPZtw==",
       "dev": true
     },
+    "@biomejs/biome": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/biome/-/biome-1.5.3.tgz",
+      "integrity": "sha512-yvZCa/g3akwTaAQ7PCwPWDCkZs3Qa5ONg/fgOUT9e6wAWsPftCjLQFPXBeGxPK30yZSSpgEmRCfpGTmVbUjGgg==",
+      "dev": true,
+      "requires": {
+        "@biomejs/cli-darwin-arm64": "1.5.3",
+        "@biomejs/cli-darwin-x64": "1.5.3",
+        "@biomejs/cli-linux-arm64": "1.5.3",
+        "@biomejs/cli-linux-arm64-musl": "1.5.3",
+        "@biomejs/cli-linux-x64": "1.5.3",
+        "@biomejs/cli-linux-x64-musl": "1.5.3",
+        "@biomejs/cli-win32-arm64": "1.5.3",
+        "@biomejs/cli-win32-x64": "1.5.3"
+      }
+    },
+    "@biomejs/cli-darwin-arm64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-darwin-arm64/-/cli-darwin-arm64-1.5.3.tgz",
+      "integrity": "sha512-ImU7mh1HghEDyqNmxEZBoMPr8SxekkZuYcs+gynKlNW+TALQs7swkERiBLkG9NR0K1B3/2uVzlvYowXrmlW8hw==",
+      "dev": true,
+      "optional": true
+    },
+    "@biomejs/cli-darwin-x64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-darwin-x64/-/cli-darwin-x64-1.5.3.tgz",
+      "integrity": "sha512-vCdASqYnlpq/swErH7FD6nrFz0czFtK4k/iLgj0/+VmZVjineFPgevOb+Sr9vz0tk0GfdQO60bSpI74zU8M9Dw==",
+      "dev": true,
+      "optional": true
+    },
+    "@biomejs/cli-linux-arm64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-arm64/-/cli-linux-arm64-1.5.3.tgz",
+      "integrity": "sha512-cupBQv0sNF1OKqBfx7EDWMSsKwRrBUZfjXawT4s6hKV6ALq7p0QzWlxr/sDmbKMLOaLQtw2Qgu/77N9rm+f9Rg==",
+      "dev": true,
+      "optional": true
+    },
+    "@biomejs/cli-linux-arm64-musl": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-arm64-musl/-/cli-linux-arm64-musl-1.5.3.tgz",
+      "integrity": "sha512-DYuMizUYUBYfS0IHGjDrOP1RGipqWfMGEvNEJ398zdtmCKLXaUvTimiox5dvx4X15mBK5M2m8wgWUgOP1giUpQ==",
+      "dev": true,
+      "optional": true
+    },
+    "@biomejs/cli-linux-x64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-x64/-/cli-linux-x64-1.5.3.tgz",
+      "integrity": "sha512-YQrSArQvcv4FYsk7Q91Yv4uuu5F8hJyORVcv3zsjCLGkjIjx2RhjYLpTL733SNL7v33GmOlZY0eFR1ko38tuUw==",
+      "dev": true,
+      "optional": true
+    },
+    "@biomejs/cli-linux-x64-musl": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-linux-x64-musl/-/cli-linux-x64-musl-1.5.3.tgz",
+      "integrity": "sha512-UUHiAnlDqr2Y/LpvshBFhUYMWkl2/Jn+bi3U6jKuav0qWbbBKU/ByHgR4+NBxpKBYoCtWxhnmatfH1bpPIuZMw==",
+      "dev": true,
+      "optional": true
+    },
+    "@biomejs/cli-win32-arm64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-win32-arm64/-/cli-win32-arm64-1.5.3.tgz",
+      "integrity": "sha512-HxatYH7vf/kX9nrD+pDYuV2GI9GV8EFo6cfKkahAecTuZLPxryHx1WEfJthp5eNsE0+09STGkKIKjirP0ufaZA==",
+      "dev": true,
+      "optional": true
+    },
+    "@biomejs/cli-win32-x64": {
+      "version": "1.5.3",
+      "resolved": "https://registry.npmjs.org/@biomejs/cli-win32-x64/-/cli-win32-x64-1.5.3.tgz",
+      "integrity": "sha512-fMvbSouZEASU7mZH8SIJSANDm5OqsjgtVXlbUqxwed6BP7uuHRSs396Aqwh2+VoW8fwTpp6ybIUoC9FrzB0kyA==",
+      "dev": true,
+      "optional": true
+    },
     "@discoveryjs/json-ext": {
       "version": "0.5.7",
       "resolved": "https://registry.npmjs.org/@discoveryjs/json-ext/-/json-ext-0.5.7.tgz",
@@ -24733,12 +24945,6 @@
       "integrity": "sha512-vkcDPrRZo1QZLbn5RLGPpg/WmIQ65qoWWhcGKf/b5eplkkarX0m9z8ppCat4mlOqUsWpyNuYgO3VRyrYHSzX5g==",
       "dev": true
     },
-    "prettier": {
-      "version": "2.8.8",
-      "resolved": "https://registry.npmjs.org/prettier/-/prettier-2.8.8.tgz",
-      "integrity": "sha512-tdN8qQGvNjw4CHbY+XXk0JgCXn9QiF21a55rBe5LJAU+kDyC4WQn4+awm2Xfk2lQMk5fKup9XgzTZtGkjBdP9Q==",
-      "dev": true
-    },
     "pretty-format": {
       "version": "27.5.1",
       "resolved": "https://registry.npmjs.org/pretty-format/-/pretty-format-27.5.1.tgz",
diff --git a/package.json b/package.json
index cfed3c3b..08bd980d 100644
--- a/package.json
+++ b/package.json
@@ -5,10 +5,10 @@
   "description": "Dashboard for Optuna",
   "main": "index.js",
   "scripts": {
-    "fmt": "prettier --write \"{optuna_dashboard/ts,typescript_tests,standalone_app/src,vscode/src}/**/*.{ts,tsx}\"",
+    "fmt": "biome format --write .",
     "lint": "npm run lint:eslint && npm run lint:fmt",
     "lint:eslint": "eslint . --ext .ts,.tsx --max-warnings 0",
-    "lint:fmt": "prettier --list-different \"{optuna_dashboard/ts,typescript_tests,standalone_app/src,vscode/src}/**/*.{ts,tsx}\"",
+    "lint:fmt": "biome format .",
     "watch": "NODE_ENV=development TYPESCRIPT_LOADER=esbuild-loader webpack --watch",
     "build": "webpack",
     "build:dev": "NODE_ENV=development TYPESCRIPT_LOADER=esbuild-loader webpack",
@@ -47,6 +47,7 @@
   "devDependencies": {
     "@babel/core": "^7.23.9",
     "@babel/preset-env": "^7.23.9",
+    "@biomejs/biome": "1.5.3",
     "@testing-library/react": "^14.1.2",
     "@types/jest": "^29.5.11",
     "@types/plotly.js": "^2.12.32",
@@ -62,7 +63,6 @@
     "jest": "^29.7.0",
     "jest-canvas-mock": "^2.5.2",
     "jest-environment-jsdom": "^29.7.0",
-    "prettier": "^2.5.1",
     "style-loader": "^3.3.4",
     "ts-jest": "^29.1.2",
     "ts-loader": "^9.5.1",
diff --git a/standalone_app/src/components/DataGrid.tsx b/standalone_app/src/components/DataGrid.tsx
index 2855f1f7..ec70e294 100644
--- a/standalone_app/src/components/DataGrid.tsx
+++ b/standalone_app/src/components/DataGrid.tsx
@@ -65,8 +65,8 @@ function DataGrid<T>(props: {
   initialRowsPerPage = initialRowsPerPage // use first element as default
     ? initialRowsPerPage
     : isNumber(rowsPerPageOption[0])
-    ? rowsPerPageOption[0]
-    : rowsPerPageOption[0].value
+      ? rowsPerPageOption[0]
+      : rowsPerPageOption[0].value
   const [rowsPerPage, setRowsPerPage] = React.useState(initialRowsPerPage)
 
   const handleChangePage = (event: unknown, newPage: number) => {
diff --git a/standalone_app/src/components/PlotHistory.tsx b/standalone_app/src/components/PlotHistory.tsx
index 0b421e5a..24f90034 100644
--- a/standalone_app/src/components/PlotHistory.tsx
+++ b/standalone_app/src/components/PlotHistory.tsx
@@ -231,8 +231,8 @@ const plotHistory = (
     return xAxis === "number"
       ? trial.number
       : xAxis === "datetime_start"
-      ? trial.datetime_start ?? new Date()
-      : trial.datetime_complete ?? new Date()
+        ? trial.datetime_start ?? new Date()
+        : trial.datetime_complete ?? new Date()
   }
 
   const getValue = (trial: Trial, objectiveId: number): number | null => {
diff --git a/standalone_app/src/sqlite3.ts b/standalone_app/src/sqlite3.ts
index d01a7e52..a0bf018b 100644
--- a/standalone_app/src/sqlite3.ts
+++ b/standalone_app/src/sqlite3.ts
@@ -174,12 +174,12 @@ const getTrials = (
         vals[2] === "COMPLETE"
           ? "Complete"
           : vals[2] === "PRUNED"
-          ? "Pruned"
-          : vals[2] === "RUNNING"
-          ? "Running"
-          : vals[2] === "WAITING"
-          ? "Waiting"
-          : "Fail"
+            ? "Pruned"
+            : vals[2] === "RUNNING"
+              ? "Running"
+              : vals[2] === "WAITING"
+                ? "Waiting"
+                : "Fail"
       const trial: Trial = {
         trial_id: trialId,
         number: vals[1],
@@ -220,8 +220,8 @@ const getTrialValues = (
           vals[1] === "INF_NEG"
             ? "-inf"
             : vals[1] === "INF_POS"
-            ? "+inf"
-            : vals[0]
+              ? "+inf"
+              : vals[0]
         )
       },
     })
@@ -391,10 +391,10 @@ const getTrialIntermediateValues = (
             vals[2] === "INF_NEG"
               ? "-inf"
               : vals[2] === "INF_POS"
-              ? "+inf"
-              : vals[2] === "NAN"
-              ? "nan"
-              : vals[1],
+                ? "+inf"
+                : vals[2] === "NAN"
+                  ? "nan"
+                  : vals[1],
         })
       },
     })