diff --git a/common/GameCommon.js b/common/GameCommon.js
index 1c6675d..0399d3e 100644
--- a/common/GameCommon.js
+++ b/common/GameCommon.js
@@ -1,5 +1,6 @@
 import Geometry from './Geometry.js'
 import Protocol from './Protocol.js'
+import Time from './Time.js'
 import Util from './Util.js'
 
 // Map<gameId, GameObject>
@@ -89,14 +90,14 @@ function playerExists(gameId, playerId) {
 }
 
 function getRelevantPlayers(gameId, ts) {
-  const minTs = ts - 30000
+  const minTs = ts - 30 * Time.SEC
   return getAllPlayers(gameId).filter(player => {
     return player.ts >= minTs || player.points > 0
   })
 }
 
 function getActivePlayers(gameId, ts) {
-  const minTs = ts - 30000
+  const minTs = ts - 30 * Time.SEC
   return getAllPlayers(gameId).filter(player => {
     return player.ts >= minTs
   })
diff --git a/common/Time.js b/common/Time.js
new file mode 100644
index 0000000..ced1bc8
--- /dev/null
+++ b/common/Time.js
@@ -0,0 +1,45 @@
+const MS = 1
+const SEC = MS * 1000
+const MIN = SEC * 60
+const HOUR = MIN * 60
+const DAY = HOUR * 24
+
+export const timestamp = () => {
+  const d = new Date();
+  return Date.UTC(
+    d.getUTCFullYear(),
+    d.getUTCMonth(),
+    d.getUTCDate(),
+    d.getUTCHours(),
+    d.getUTCMinutes(),
+    d.getUTCSeconds(),
+    d.getUTCMilliseconds(),
+  )
+}
+
+export const timeDiffStr = (from, to) => {
+  let diff = to - from
+  const d = Math.floor(diff / DAY)
+  diff = diff % DAY
+
+  const h = Math.floor(diff / HOUR)
+  diff = diff % HOUR
+
+  const m = Math.floor(diff / MIN)
+  diff = diff % MIN
+
+  const s = Math.floor(diff / SEC)
+
+  return `${d}d ${h}h ${m}m ${s}s`
+}
+
+export default {
+  MS,
+  SEC,
+  MIN,
+  HOUR,
+  DAY,
+
+  timestamp,
+  timeDiffStr,
+}
diff --git a/common/Util.js b/common/Util.js
index 3354bb7..144067e 100644
--- a/common/Util.js
+++ b/common/Util.js
@@ -69,19 +69,6 @@ export const shuffle = (
   return arr
 }
 
-export const timestamp = () => {
-  const d = new Date();
-  return Date.UTC(
-    d.getUTCFullYear(),
-    d.getUTCMonth(),
-    d.getUTCDate(),
-    d.getUTCHours(),
-    d.getUTCMinutes(),
-    d.getUTCSeconds(),
-    d.getUTCMilliseconds(),
-  )
-}
-
 function encodeShape(data) {
   if (typeof data === 'number') {
       return data
@@ -224,7 +211,6 @@ export default {
   choice,
   throttle,
   shuffle,
-  timestamp,
 
   encodeShape,
   decodeShape,
diff --git a/game/WsWrapper.js b/game/WsWrapper.js
index add6722..10ead38 100644
--- a/game/WsWrapper.js
+++ b/game/WsWrapper.js
@@ -1,3 +1,5 @@
+import Time from '../common/Time.js'
+
 /**
  * Wrapper around ws that
  * - buffers 'send' until a connection is available
@@ -48,12 +50,12 @@ export default class WsWrapper {
     }
     ws.onerror = (e) => {
       this.handle = null
-      this.reconnectTimeout = setTimeout(() => { this.connect() }, 1000)
+      this.reconnectTimeout = setTimeout(() => { this.connect() }, 1 * Time.SEC)
       this.onclose(e)
     }
     ws.onclose = (e) => {
       this.handle = null
-      this.reconnectTimeout = setTimeout(() => { this.connect() }, 1000)
+      this.reconnectTimeout = setTimeout(() => { this.connect() }, 1 * Time.SEC)
       this.onclose(e)
     }
   }
diff --git a/game/game.js b/game/game.js
index ad363d7..18c0088 100644
--- a/game/game.js
+++ b/game/game.js
@@ -9,6 +9,7 @@ import PuzzleGraphics from './PuzzleGraphics.js'
 import Game from './Game.js'
 import fireworksController from './Fireworks.js'
 import Protocol from '../common/Protocol.js'
+import Time from '../common/Time.js'
 
 if (typeof GAME_ID === 'undefined') throw '[ GAME_ID not set ]'
 if (typeof WS_ADDRESS === 'undefined') throw '[ WS_ADDRESS not set ]'
@@ -18,7 +19,7 @@ if (typeof DEBUG === 'undefined') window.DEBUG = false
 
 let RERENDER = true
 
-let TIME = () => Util.timestamp()
+let TIME = () => Time.timestamp()
 
 function addCanvasToDom(canvas) {
   canvas.width = window.innerWidth
@@ -154,7 +155,7 @@ function addMenuToDom(gameId) {
   const scoresListEl = document.createElement('table')
   const updateScores = () => {
     const ts = TIME()
-    const minTs = ts - 30000
+    const minTs = ts - 30 * Time.SEC
 
     const players = Game.getRelevantPlayers(gameId, ts)
     const actives = players.filter(player => player.ts >= minTs)
@@ -187,31 +188,11 @@ function addMenuToDom(gameId) {
   const timerStr = () => {
     const started = Game.getStartTs(gameId)
     const ended = Game.getFinishTs(gameId)
-
     const icon = ended ? '🏁' : '⏳'
-
     const from = started;
     const to = ended || TIME()
-
-    const MS = 1
-    const SEC = MS * 1000
-    const MIN = SEC * 60
-    const HOUR = MIN * 60
-    const DAY = HOUR * 24
-
-    let diff = to - from
-    const d = Math.floor(diff / DAY)
-    diff = diff % DAY
-
-    const h = Math.floor(diff / HOUR)
-    diff = diff % HOUR
-
-    const m = Math.floor(diff / MIN)
-    diff = diff % MIN
-
-    const s = Math.floor(diff / SEC)
-
-    return `${icon} ${d}d ${h}h ${m}m ${s}s`
+    const timeDiffStr = Time.timeDiffStr(from, to)
+    return `${icon} ${timeDiffStr}`
   }
 
   const timerCountdownEl = document.createElement('div')
@@ -372,7 +353,7 @@ async function main() {
     const {game, log} = await Communication.connectReplay(gameId, CLIENT_ID)
     Game.newGame(Util.decodeGame(game))
     GAME_LOG = log
-    lastRealTime = Util.timestamp()
+    lastRealTime = Time.timestamp()
     GAME_START_TS = GAME_LOG[0][GAME_LOG[0].length - 1]
     lastGameTime = GAME_START_TS
     TIME = () => lastGameTime
@@ -440,7 +421,7 @@ async function main() {
       evts.addEvent([Protocol.INPUT_EV_PLAYER_NAME, nameChangeEl.value])
     })
   } else if (MODE === 'replay') {
-    let setSpeedStatus = () => {
+    const setSpeedStatus = () => {
       replayControl.speed.innerText = 'Replay-Speed: ' + (REPLAY_SPEEDS[REPLAY_SPEED_IDX] + 'x') + (REPLAY_PAUSED ? ' Paused' : '')
     }
     setSpeedStatus()
@@ -494,7 +475,7 @@ async function main() {
     // no external communication for replay mode,
     // only the GAME_LOG is relevant
     let inter = setInterval(() => {
-      let realTime = Util.timestamp()
+      let realTime = Time.timestamp()
       if (REPLAY_PAUSED) {
         lastRealTime = realTime
         return
diff --git a/game/index.js b/game/index.js
index cd288e0..e5d4823 100644
--- a/game/index.js
+++ b/game/index.js
@@ -1,3 +1,5 @@
+import Time from '../common/Time.js'
+
 const Upload = {
   name: 'upload',
   props: {
@@ -26,20 +28,6 @@ const Upload = {
   }
 }
 
-
-export const timestamp = () => {
-  const d = new Date();
-  return Date.UTC(
-    d.getUTCFullYear(),
-    d.getUTCMonth(),
-    d.getUTCDate(),
-    d.getUTCHours(),
-    d.getUTCMinutes(),
-    d.getUTCSeconds(),
-    d.getUTCMilliseconds(),
-  )
-}
-
 export default {
   components: {
     Upload,
@@ -104,29 +92,10 @@ export default {
   methods: {
     time(start, end) {
       const icon = end ? '🏁' : '⏳'
-
       const from = start;
-      const to = end || timestamp()
-
-      const MS = 1
-      const SEC = MS * 1000
-      const MIN = SEC * 60
-      const HOUR = MIN * 60
-      const DAY = HOUR * 24
-
-      let diff = to - from
-      const d = Math.floor(diff / DAY)
-      diff = diff % DAY
-
-      const h = Math.floor(diff / HOUR)
-      diff = diff % HOUR
-
-      const m = Math.floor(diff / MIN)
-      diff = diff % MIN
-
-      const s = Math.floor(diff / SEC)
-
-      return `${icon} ${d}d ${h}h ${m}m ${s}s`
+      const to = end || Time.timestamp()
+      const timeDiffStr = Time.timeDiffStr(from, to)
+      return `${icon} ${timeDiffStr}`
     },
     mediaImgUploaded(j) {
       this.image = j.image
diff --git a/server/index.js b/server/index.js
index 05a7fe8..fc830ac 100644
--- a/server/index.js
+++ b/server/index.js
@@ -12,6 +12,7 @@ import bodyParser from 'body-parser'
 import v8 from 'v8'
 import GameLog from './GameLog.js'
 import GameSockets from './GameSockets.js'
+import Time from '../common/Time.js'
 
 const log = logger('index.js')
 
@@ -80,7 +81,7 @@ app.post('/newgame', bodyParser.json(), async (req, res) => {
   log.log(req.body.tiles, req.body.image)
   const gameId = Util.uniqId()
   if (!Game.exists(gameId)) {
-    const ts = Util.timestamp()
+    const ts = Time.timestamp()
     await Game.createGame(gameId, req.body.tiles, req.body.image, ts)
   }
   res.send({ url: `/g/${gameId}` })
@@ -90,7 +91,7 @@ app.use('/common/', express.static('./../common/'))
 app.use('/uploads/', express.static('./../data/uploads/'))
 app.use('/', async (req, res, next) => {
   if (req.path === '/') {
-    const ts = Util.timestamp()
+    const ts = Time.timestamp()
     const games = [
       ...Game.getAllGames().map(game => ({
         id: game.id,
@@ -162,7 +163,7 @@ wss.on('message', async ({socket, data}) => {
         if (!Game.exists(gameId)) {
           throw `[game ${gameId} does not exist... ]`
         }
-        const ts = Util.timestamp()
+        const ts = Time.timestamp()
         Game.addPlayer(gameId, clientId, ts)
         GameSockets.addSocket(gameId, socket)
         const game = Game.get(gameId)
@@ -178,7 +179,7 @@ wss.on('message', async ({socket, data}) => {
         }
         const clientSeq = msg[1]
         const clientEvtData = msg[2]
-        const ts = Util.timestamp()
+        const ts = Time.timestamp()
 
         let sendGame = false
         if (!Game.playerExists(gameId, clientId)) {