diff --git a/.github/workflows/translation-check.yml b/.github/workflows/translation-check.yml
index ed8fab7f19..f1ff5bced8 100644
--- a/.github/workflows/translation-check.yml
+++ b/.github/workflows/translation-check.yml
@@ -5,13 +5,17 @@ on:
   pull_request:
     paths:
       - "src/translation/wininstaller/**"
+      - "src/translation/*.ts"
       - "tools/check-wininstaller-translations.sh"
+      - "tools/check-translations.py"
       - ".github/workflows/translation-check.yml"
   push:
     paths:
-      - "src/translation/wininstaller/**"
-      - "tools/check-wininstaller-translations.sh"
-      - ".github/workflows/translation-check.yml"
+      - 'src/translation/wininstaller/**'
+      - 'src/translation/*.ts'
+      - 'tools/check-wininstaller-translations.sh'
+      - 'tools/check-translations.py'
+      - '.github/workflows/translation-check.yml'
 
 jobs:
   translation-check:
@@ -26,3 +30,5 @@ jobs:
         run: ./tools/check-wininstaller-translations.sh
       - name: "Check for duplicate hotkeys (will not fail)"
         run: perl ./tools/checkkeys.pl
+      - name: "Check application translations"
+        run: ./tools/check-translations.py --ts-dir src/translation
diff --git a/tools/check-translations.py b/tools/check-translations.py
new file mode 100755
index 0000000000..d9c2dd02d0
--- /dev/null
+++ b/tools/check-translations.py
@@ -0,0 +1,274 @@
+#!/usr/bin/env python3
+#
+##############################################################################
+# Copyright (c) 2026
+#
+# Author(s):
+# ChatGPT
+# ann0see
+# JaminShanti
+# Gemini
+# The Jamulus Development Team
+#
+##############################################################################
+#
+# This program is free software: you can redistribute it and/or modify it under
+# the terms of the GNU Affero General Public License as published by the Free
+# Software Foundation, either version 3 of the License, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <https://www.gnu.org/licenses/>.
+#
+##############################################################################
+
+"""
+Qt TS translation checker.
+
+This tool validates Qt `.ts` translation files according to Qt Linguist
+semantics.
+"""
+
+import argparse
+import re
+import sys
+import xml.etree.ElementTree as ET
+import xml.sax
+from collections import defaultdict, Counter
+from dataclasses import dataclass
+from enum import IntEnum
+from pathlib import Path
+
+# Regex helpers
+PLACEHOLDER_RE = re.compile(r"%\d+")
+HTML_TAG_RE = re.compile(r"<[^>]+>")
+
+
+class Colors:
+    """ANSI escape codes for terminal output."""
+    BOLD = "\033[1m"
+    CYAN = "\033[36m"
+    YELLOW = "\033[33m"
+    RED = "\033[31m"
+    RESET = "\033[0m"
+
+
+def configure_colors(color_arg: str):
+    """Disable color constants if outputting to a non-TTY without 'always' override."""
+    if color_arg == 'never' or (color_arg == 'auto' and not sys.stdout.isatty()):
+        Colors.BOLD = Colors.CYAN = Colors.YELLOW = Colors.RED = Colors.RESET = ""
+
+
+class Severity(IntEnum):
+    WARNING = 1
+    SEVERE = 2
+
+
+@dataclass(frozen=True)
+class MessageContext:
+    ts_file: Path
+    line: int
+    lang: str
+    source: str
+    translation: str
+    tr_type: str
+    excerpt: str
+
+
+@dataclass(frozen=True)
+class WarningItem:
+    ts_file: Path
+    line: int
+    lang: str
+    message: str
+    severity: Severity
+
+
+class MessageLocator(xml.sax.ContentHandler):
+    """SAX handler to find exact line numbers of <message> elements."""
+
+    def __init__(self):
+        super().__init__()
+        self.lines = []
+        self.locator = None
+
+    def setDocumentLocator(self, locator):
+        self.locator = locator
+
+    def startElement(self, name, attrs):
+        if name == "message" and self.locator:
+            self.lines.append(self.locator.getLineNumber())
+
+
+def get_exact_message_lines(text: str):
+    """Yield exact line numbers for <message> elements using a SAX parser."""
+    handler = MessageLocator()
+    try:
+        xml.sax.parseString(text.encode("utf-8"), handler)
+    except xml.sax.SAXException:
+        pass
+    yield from handler.lines
+
+
+def check_language_header(ts_file: Path, root, file_lang: str):
+    header_lang = root.attrib.get("language", "")
+    if header_lang != file_lang:
+        msg = f"Language header mismatch '{header_lang}' != '{file_lang}'"
+        return [WarningItem(ts_file, 0, file_lang, msg, Severity.WARNING)]
+    return []
+
+
+def check_empty_translation(ctx: MessageContext):
+    if not ctx.translation.strip() and ctx.tr_type != "unfinished":
+        msg = f"Empty translation for '{ctx.excerpt}'"
+        return [WarningItem(ctx.ts_file, ctx.line, ctx.lang, msg, Severity.SEVERE)]
+    return []
+
+
+def check_placeholders(ctx: MessageContext):
+    if ctx.tr_type == "unfinished":
+        return []
+    src_cnt = Counter(PLACEHOLDER_RE.findall(ctx.source))
+    tr_cnt = Counter(PLACEHOLDER_RE.findall(ctx.translation))
+    if src_cnt != tr_cnt:
+        msg = (f"Placeholder mismatch for '{ctx.excerpt}'\n"
+               f"Source: {ctx.source}\nTrans:  {ctx.translation}")
+        return [WarningItem(ctx.ts_file, ctx.line, ctx.lang, msg, Severity.WARNING)]
+    return []
+
+
+def check_html(ctx: MessageContext):
+    if (HTML_TAG_RE.search(ctx.source) and not HTML_TAG_RE.search(ctx.translation)
+        and ctx.tr_type != "unfinished"):
+        msg = (f"HTML missing for '{ctx.excerpt}'\n"
+               f"Source: {ctx.source}\nTrans:  {ctx.translation}")
+        return [WarningItem(ctx.ts_file, ctx.line, ctx.lang, msg, Severity.WARNING)]
+    return []
+
+
+def check_whitespace(ctx: MessageContext):
+    if not ctx.translation or ctx.tr_type == "unfinished":
+        return []
+    src_lead = ctx.source != ctx.source.lstrip()
+    src_trail = ctx.source != ctx.source.rstrip()
+    tr_lead = ctx.translation != ctx.translation.lstrip()
+    tr_trail = ctx.translation != ctx.translation.rstrip()
+    if src_lead != tr_lead or src_trail != tr_trail:
+        msg = f"Leading/trailing whitespace mismatch for '{ctx.excerpt}'"
+        return [WarningItem(ctx.ts_file, ctx.line, ctx.lang, msg, Severity.WARNING)]
+    return []
+
+
+def check_newline_consistency(ctx: MessageContext):
+    if ctx.source.endswith("\n") != ctx.translation.endswith("\n"):
+        msg = f"Newline mismatch for '{ctx.excerpt}'"
+        return [WarningItem(ctx.ts_file, ctx.line, ctx.lang, msg, Severity.WARNING)]
+    return []
+
+
+def _extract_message_data(message):
+    src_node = message.find("source")
+    source = "".join(src_node.itertext()) if src_node is not None else ""
+    tr_elem = message.find("translation")
+    tr_type, translation = "", ""
+    if tr_elem is not None:
+        tr_type = tr_elem.attrib.get("type", "")
+        forms = tr_elem.findall("numerusform")
+        if forms:
+            translation = " ".join("".join(n.itertext()) for n in forms)
+        else:
+            translation = "".join(tr_elem.itertext())
+    return source, translation, tr_type
+
+
+def _process_context(ts_file, file_lang, context, line_gen):
+    warnings = []
+    for message in context.findall("message"):
+        line = next(line_gen, 0)
+        src, trans, tr_type = _extract_message_data(message)
+        clean = src.strip().replace("\n", " ")
+        excerpt = clean[:30] + ("..." if len(clean) > 30 else "")
+        ctx = MessageContext(ts_file, line, file_lang, src, trans, tr_type, excerpt)
+        if ctx.tr_type not in {"vanished", "obsolete"}:
+            for check in [check_empty_translation, check_placeholders, check_html,
+                          check_whitespace, check_newline_consistency]:
+                warnings.extend(check(ctx))
+
+    return warnings
+
+
+def detect_warnings(ts_file: Path, file_lang: str):
+    try:
+        text = ts_file.read_text(encoding="utf-8")
+        root = ET.fromstring(text)
+    except (OSError, ET.ParseError) as exc:
+        return [WarningItem(ts_file, 0, file_lang, f"Error parsing XML: {exc}", Severity.SEVERE)]
+
+    warnings = check_language_header(ts_file, root, file_lang)
+    line_gen = get_exact_message_lines(text)
+    for context in root.findall("context"):
+        warnings.extend(_process_context(ts_file, file_lang, context, line_gen))
+    return warnings
+
+
+def _print_results(grouped):
+    for file in sorted(grouped.keys()):
+        print(f"\n{Colors.BOLD}File: {file.name}{Colors.RESET}")
+        for w in sorted(grouped[file], key=lambda x: x.line):
+            is_severe = w.severity == Severity.SEVERE
+            color = Colors.RED if is_severe else Colors.YELLOW
+            sev = "SEVERE " if is_severe else "WARNING"
+
+            lines = w.message.split("\n")
+            prefix = f"  {Colors.CYAN}Line {w.line:<4}{Colors.RESET}"
+
+            print(f"{prefix} | {color}{sev}{Colors.RESET} | {lines[0]}")
+            for extra in lines[1:]:
+                print(f"            |         | {extra}")
+
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--ts-dir", type=Path, default=Path("../src/translation"))
+    parser.add_argument("--strict", action="store_true")
+    parser.add_argument("--color", choices=["never", "auto", "always"], default="auto",
+                        help=("Control color output. 'auto' (default) "
+                              "uses colors only if output is a TTY."))
+    args = parser.parse_args()
+
+    configure_colors(args.color)
+
+    ts_files = sorted(args.ts_dir.glob("translation_*.ts"))
+    if not ts_files:
+        print("Error: No translation files found in the specified directory.", file=sys.stderr)
+        return 2
+
+    all_warnings, stats = [], defaultdict(lambda: {"severe": 0, "warning": 0})
+    for f in ts_files:
+        all_warnings.extend(detect_warnings(f, f.stem.replace("translation_", "")))
+
+    grouped = defaultdict(list)
+    for w in all_warnings:
+        grouped[w.ts_file].append(w)
+        stats[w.lang]["severe" if w.severity == Severity.SEVERE else "warning"] += 1
+
+    _print_results(grouped)
+
+    print("\n== Test Summary ==")
+    for lang in sorted(stats.keys()):
+        print(f"{Colors.BOLD}[{lang}]{Colors.RESET} Severe: {stats[lang]['severe']}, "
+              f"Warnings: {stats[lang]['warning']}")
+
+    if sum(s["severe"] for s in stats.values()) > 0 or (
+        args.strict and sum(s["warning"] for s in stats.values()) > 0):
+        return 1
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())