diff --git a/models/issues/stopwatch.go b/models/issues/stopwatch.go
index 629af95b57..7c05a3a883 100644
--- a/models/issues/stopwatch.go
+++ b/models/issues/stopwatch.go
@@ -46,11 +46,6 @@ func (s Stopwatch) Seconds() int64 {
 	return int64(timeutil.TimeStampNow() - s.CreatedUnix)
 }
 
-// Duration returns a human-readable duration string based on local server time
-func (s Stopwatch) Duration() string {
-	return util.SecToTime(s.Seconds())
-}
-
 func getStopwatch(ctx context.Context, userID, issueID int64) (sw *Stopwatch, exists bool, err error) {
 	sw = new(Stopwatch)
 	exists, err = db.GetEngine(ctx).
@@ -201,7 +196,7 @@ func FinishIssueStopwatch(ctx context.Context, user *user_model.User, issue *Iss
 		Doer:    user,
 		Issue:   issue,
 		Repo:    issue.Repo,
-		Content: util.SecToTime(timediff),
+		Content: util.SecToHours(timediff),
 		Type:    CommentTypeStopTracking,
 		TimeID:  tt.ID,
 	}); err != nil {
diff --git a/modules/templates/helper.go b/modules/templates/helper.go
index 609407d36b..a2cc166de9 100644
--- a/modules/templates/helper.go
+++ b/modules/templates/helper.go
@@ -69,7 +69,7 @@ func NewFuncMap() template.FuncMap {
 		// time / number / format
 		"FileSize": base.FileSize,
 		"CountFmt": countFmt,
-		"Sec2Time": util.SecToTime,
+		"Sec2Time": util.SecToHours,
 
 		"TimeEstimateString": timeEstimateString,
 
diff --git a/modules/util/sec_to_time.go b/modules/util/sec_to_time.go
index ad0fb1a68b..73667d723e 100644
--- a/modules/util/sec_to_time.go
+++ b/modules/util/sec_to_time.go
@@ -8,59 +8,17 @@ import (
 	"strings"
 )
 
-// SecToTime converts an amount of seconds to a human-readable string. E.g.
-// 66s			-> 1 minute 6 seconds
-// 52410s		-> 14 hours 33 minutes
-// 563418		-> 6 days 12 hours
-// 1563418		-> 2 weeks 4 days
-// 3937125s     -> 1 month 2 weeks
-// 45677465s	-> 1 year 6 months
-func SecToTime(durationVal any) string {
+// SecToHours converts an amount of seconds to a human-readable hours string.
+// This is stable for planning and managing timesheets.
+// Here it only supports hours and minutes, because a work day could contain 6 or 7 or 8 hours.
+func SecToHours(durationVal any) string {
 	duration, _ := ToInt64(durationVal)
+	hours := duration / 3600
+	minutes := (duration / 60) % 60
 
 	formattedTime := ""
-
-	// The following four variables are calculated by taking
-	// into account the previously calculated variables, this avoids
-	// pitfalls when using remainders. As that could lead to incorrect
-	// results when the calculated number equals the quotient number.
-	remainingDays := duration / (60 * 60 * 24)
-	years := remainingDays / 365
-	remainingDays -= years * 365
-	months := remainingDays * 12 / 365
-	remainingDays -= months * 365 / 12
-	weeks := remainingDays / 7
-	remainingDays -= weeks * 7
-	days := remainingDays
-
-	// The following three variables are calculated without depending
-	// on the previous calculated variables.
-	hours := (duration / 3600) % 24
-	minutes := (duration / 60) % 60
-	seconds := duration % 60
-
-	// Extract only the relevant information of the time
-	// If the time is greater than a year, it makes no sense to display seconds.
-	switch {
-	case years > 0:
-		formattedTime = formatTime(years, "year", formattedTime)
-		formattedTime = formatTime(months, "month", formattedTime)
-	case months > 0:
-		formattedTime = formatTime(months, "month", formattedTime)
-		formattedTime = formatTime(weeks, "week", formattedTime)
-	case weeks > 0:
-		formattedTime = formatTime(weeks, "week", formattedTime)
-		formattedTime = formatTime(days, "day", formattedTime)
-	case days > 0:
-		formattedTime = formatTime(days, "day", formattedTime)
-		formattedTime = formatTime(hours, "hour", formattedTime)
-	case hours > 0:
-		formattedTime = formatTime(hours, "hour", formattedTime)
-		formattedTime = formatTime(minutes, "minute", formattedTime)
-	default:
-		formattedTime = formatTime(minutes, "minute", formattedTime)
-		formattedTime = formatTime(seconds, "second", formattedTime)
-	}
+	formattedTime = formatTime(hours, "hour", formattedTime)
+	formattedTime = formatTime(minutes, "minute", formattedTime)
 
 	// The formatTime() function always appends a space at the end. This will be trimmed
 	return strings.TrimRight(formattedTime, " ")
@@ -76,6 +34,5 @@ func formatTime(value int64, name, formattedTime string) string {
 	} else if value > 1 {
 		formattedTime = fmt.Sprintf("%s%d %ss ", formattedTime, value, name)
 	}
-
 	return formattedTime
 }
diff --git a/modules/util/sec_to_time_test.go b/modules/util/sec_to_time_test.go
index 4d1213a52c..71a8801d4f 100644
--- a/modules/util/sec_to_time_test.go
+++ b/modules/util/sec_to_time_test.go
@@ -9,22 +9,17 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestSecToTime(t *testing.T) {
+func TestSecToHours(t *testing.T) {
 	second := int64(1)
 	minute := 60 * second
 	hour := 60 * minute
 	day := 24 * hour
-	year := 365 * day
 
-	assert.Equal(t, "1 minute 6 seconds", SecToTime(minute+6*second))
-	assert.Equal(t, "1 hour", SecToTime(hour))
-	assert.Equal(t, "1 hour", SecToTime(hour+second))
-	assert.Equal(t, "14 hours 33 minutes", SecToTime(14*hour+33*minute+30*second))
-	assert.Equal(t, "6 days 12 hours", SecToTime(6*day+12*hour+30*minute+18*second))
-	assert.Equal(t, "2 weeks 4 days", SecToTime((2*7+4)*day+2*hour+16*minute+58*second))
-	assert.Equal(t, "4 weeks", SecToTime(4*7*day))
-	assert.Equal(t, "4 weeks 1 day", SecToTime((4*7+1)*day))
-	assert.Equal(t, "1 month 2 weeks", SecToTime((6*7+3)*day+13*hour+38*minute+45*second))
-	assert.Equal(t, "11 months", SecToTime(year-25*day))
-	assert.Equal(t, "1 year 5 months", SecToTime(year+163*day+10*hour+11*minute+5*second))
+	assert.Equal(t, "1 minute", SecToHours(minute+6*second))
+	assert.Equal(t, "1 hour", SecToHours(hour))
+	assert.Equal(t, "1 hour", SecToHours(hour+second))
+	assert.Equal(t, "14 hours 33 minutes", SecToHours(14*hour+33*minute+30*second))
+	assert.Equal(t, "156 hours 30 minutes", SecToHours(6*day+12*hour+30*minute+18*second))
+	assert.Equal(t, "98 hours 16 minutes", SecToHours(4*day+2*hour+16*minute+58*second))
+	assert.Equal(t, "672 hours", SecToHours(4*7*day))
 }
diff --git a/routers/web/repo/issue_timetrack.go b/routers/web/repo/issue_timetrack.go
index 36e931a48f..134ded82d1 100644
--- a/routers/web/repo/issue_timetrack.go
+++ b/routers/web/repo/issue_timetrack.go
@@ -81,7 +81,7 @@ func DeleteTime(c *context.Context) {
 		return
 	}
 
-	c.Flash.Success(c.Tr("repo.issues.del_time_history", util.SecToTime(t.Time)))
+	c.Flash.Success(c.Tr("repo.issues.del_time_history", util.SecToHours(t.Time)))
 	c.JSONRedirect("")
 }
 
diff --git a/services/convert/issue.go b/services/convert/issue.go
index e3124efd64..37935accca 100644
--- a/services/convert/issue.go
+++ b/services/convert/issue.go
@@ -16,6 +16,7 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	api "code.gitea.io/gitea/modules/structs"
+	"code.gitea.io/gitea/modules/util"
 )
 
 func ToIssue(ctx context.Context, doer *user_model.User, issue *issues_model.Issue) *api.Issue {
@@ -186,7 +187,7 @@ func ToStopWatches(ctx context.Context, sws []*issues_model.Stopwatch) (api.Stop
 		result = append(result, api.StopWatch{
 			Created:       sw.CreatedUnix.AsTime(),
 			Seconds:       sw.Seconds(),
-			Duration:      sw.Duration(),
+			Duration:      util.SecToHours(sw.Seconds()),
 			IssueIndex:    issue.Index,
 			IssueTitle:    issue.Title,
 			RepoOwnerName: repo.OwnerName,
diff --git a/services/convert/issue_comment.go b/services/convert/issue_comment.go
index b8527ae233..9ad584a62f 100644
--- a/services/convert/issue_comment.go
+++ b/services/convert/issue_comment.go
@@ -74,7 +74,7 @@ func ToTimelineComment(ctx context.Context, repo *repo_model.Repository, c *issu
 			c.Content[0] == '|' {
 			// TimeTracking Comments from v1.21 on store the seconds instead of an formatted string
 			// so we check for the "|" delimiter and convert new to legacy format on demand
-			c.Content = util.SecToTime(c.Content[1:])
+			c.Content = util.SecToHours(c.Content[1:])
 		}
 
 		if c.Type == issues_model.CommentTypeChangeTimeEstimate {
diff --git a/web_src/js/features/stopwatch.ts b/web_src/js/features/stopwatch.ts
index af52be4e24..46168b2cd7 100644
--- a/web_src/js/features/stopwatch.ts
+++ b/web_src/js/features/stopwatch.ts
@@ -1,6 +1,6 @@
 import {createTippy} from '../modules/tippy.ts';
 import {GET} from '../modules/fetch.ts';
-import {hideElem, showElem} from '../utils/dom.ts';
+import {hideElem, queryElems, showElem} from '../utils/dom.ts';
 import {logoutFromWorker} from '../modules/worker.ts';
 
 const {appSubUrl, notificationSettings, enableTimeTracking, assetVersionEncoded} = window.config;
@@ -144,23 +144,10 @@ function updateStopwatchData(data) {
   return Boolean(data.length);
 }
 
-// TODO: This flickers on page load, we could avoid this by making a custom
-// element to render time periods. Feeding a datetime in backend does not work
-// when time zone between server and client differs.
-function updateStopwatchTime(seconds) {
-  if (!Number.isFinite(seconds)) return;
-  const datetime = (new Date(Date.now() - seconds * 1000)).toISOString();
-  for (const parent of document.querySelectorAll('.header-stopwatch-dot')) {
-    const existing = parent.querySelector(':scope > relative-time');
-    if (existing) {
-      existing.setAttribute('datetime', datetime);
-    } else {
-      const el = document.createElement('relative-time');
-      el.setAttribute('format', 'micro');
-      el.setAttribute('datetime', datetime);
-      el.setAttribute('lang', 'en-US');
-      el.setAttribute('title', ''); // make <relative-time> show no title and therefor no tooltip
-      parent.append(el);
-    }
-  }
+// TODO: This flickers on page load, we could avoid this by making a custom element to render time periods.
+function updateStopwatchTime(seconds: number) {
+  const hours = seconds / 3600 || 0;
+  const minutes = seconds / 60 || 0;
+  const timeText = hours >= 1 ? `${Math.round(hours)}h` : `${Math.round(minutes)}m`;
+  queryElems(document, '.header-stopwatch-dot', (el) => el.textContent = timeText);
 }