diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index f98a3dcac..ac9f882e2 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -15,3 +15,5 @@ db241feaa445375dc05e189e69287000ffe5fa8e
 7577dd7603f7cb3a09922d1edb65b6eafb6e2ac7
 # Indent Jinja templates, HTML, CSS, and JS via DjHTML
 4af40e80772a58eac8969360e5caeb99e3e26e78
+# Ruff UP031: Use F-string format specifiers instead of percent format
+30bde3823f50b9ba8ac5996c1c46bb72031aa6b8
diff --git a/pelican/contents.py b/pelican/contents.py
index 21c662963..cf13dabcb 100644
--- a/pelican/contents.py
+++ b/pelican/contents.py
@@ -250,7 +250,7 @@ def _expand_settings(self, key: str, klass: Optional[str] = None) -> str:
     def get_url_setting(self, key: str) -> str:
         if hasattr(self, "override_" + key):
             return getattr(self, "override_" + key)
-        key = key if self.in_default_lang else "lang_%s" % key
+        key = key if self.in_default_lang else f"lang_{key}"
         return self._expand_settings(key)
 
     def _link_replacer(self, siteurl: str, m: re.Match) -> str:
diff --git a/pelican/generators.py b/pelican/generators.py
index a2bf2f448..73b517132 100644
--- a/pelican/generators.py
+++ b/pelican/generators.py
@@ -537,9 +537,9 @@ def generate_direct_templates(self, write):
         """Generate direct templates pages"""
         for template in self.settings["DIRECT_TEMPLATES"]:
             save_as = self.settings.get(
-                "%s_SAVE_AS" % template.upper(), "%s.html" % template
+                f"{template.upper()}_SAVE_AS", f"{template}.html"
             )
-            url = self.settings.get("%s_URL" % template.upper(), "%s.html" % template)
+            url = self.settings.get(f"{template.upper()}_URL", f"{template}.html")
             if not save_as:
                 continue
 
diff --git a/pelican/settings.py b/pelican/settings.py
index 214d88a3c..46b761a51 100644
--- a/pelican/settings.py
+++ b/pelican/settings.py
@@ -591,7 +591,7 @@ def configure_settings(settings: Settings) -> Settings:
         if os.path.exists(theme_path):
             settings["THEME"] = theme_path
         else:
-            raise Exception("Could not find the theme %s" % settings["THEME"])
+            raise Exception("Could not find the theme {}".format(settings["THEME"]))
 
     # standardize strings to lowercase strings
     for key in ["DEFAULT_LANG"]:
diff --git a/pelican/tests/test_contents.py b/pelican/tests/test_contents.py
index d248c3bb6..81f8907c7 100644
--- a/pelican/tests/test_contents.py
+++ b/pelican/tests/test_contents.py
@@ -282,7 +282,7 @@ def test_datetime(self):
             #
             # Until we find some other method to test this functionality, we
             # will simply skip this test.
-            unittest.skip("There is no locale %s in this system." % locale)
+            unittest.skip(f"There is no locale {locale} in this system.")
 
     def test_template(self):
         # Pages default to page, metadata overwrites
diff --git a/pelican/tests/test_importer.py b/pelican/tests/test_importer.py
index 0349a175e..10b0f7f69 100644
--- a/pelican/tests/test_importer.py
+++ b/pelican/tests/test_importer.py
@@ -148,7 +148,7 @@ def test_dirpage_directive_for_page_kind(self):
         test_post = filter(lambda p: p[0].startswith("Empty Page"), self.posts)
         with temporary_folder() as temp:
             fname = next(iter(silent_f2p(test_post, "markdown", temp, dirpage=True)))
-            self.assertTrue(fname.endswith("pages%sempty.md" % os.path.sep))
+            self.assertTrue(fname.endswith(f"pages{os.path.sep}empty.md"))
 
     def test_dircat(self):
         silent_f2p = mute(True)(fields2pelican)
diff --git a/pelican/tests/test_pelican.py b/pelican/tests/test_pelican.py
index 075f55ebe..ba03b529d 100644
--- a/pelican/tests/test_pelican.py
+++ b/pelican/tests/test_pelican.py
@@ -71,8 +71,7 @@ def assertDirsEqual(self, left_path, right_path, msg=None):
         if proc.returncode != 0:
             msg = self._formatMessage(
                 msg,
-                "%s and %s differ:\nstdout:\n%s\nstderr\n%s"
-                % (left_path, right_path, out, err),
+                f"{left_path} and {right_path} differ:\nstdout:\n{out}\nstderr\n{err}",
             )
             raise self.failureException(msg)
 
diff --git a/pelican/tests/test_readers.py b/pelican/tests/test_readers.py
index 928eb2635..ec366fa84 100644
--- a/pelican/tests/test_readers.py
+++ b/pelican/tests/test_readers.py
@@ -27,8 +27,7 @@ def assertDictHasSubset(self, dictionary, subset):
                 self.assertEqual(
                     value,
                     real_value,
-                    "Expected %s to have value %s, but was %s"
-                    % (key, value, real_value),
+                    f"Expected {key} to have value {value}, but was {real_value}",
                 )
             else:
                 self.fail(f"Expected {key} to have value {value}, but was not in Dict")
diff --git a/pelican/tests/test_utils.py b/pelican/tests/test_utils.py
index beda71406..f7f11ffbf 100644
--- a/pelican/tests/test_utils.py
+++ b/pelican/tests/test_utils.py
@@ -721,11 +721,11 @@ def _create_dir(self, *path):
 
     def _exist_file(self, *path):
         path = os.path.join(self.root_dir, *path)
-        self.assertTrue(os.path.isfile(path), "File does not exist: %s" % path)
+        self.assertTrue(os.path.isfile(path), f"File does not exist: {path}")
 
     def _exist_dir(self, *path):
         path = os.path.join(self.root_dir, *path)
-        self.assertTrue(os.path.exists(path), "Directory does not exist: %s" % path)
+        self.assertTrue(os.path.exists(path), f"Directory does not exist: {path}")
 
     def test_copy_file_same_path(self):
         self._create_file("a.txt")
diff --git a/pelican/tools/pelican_import.py b/pelican/tools/pelican_import.py
index 39504edbe..65517f42a 100755
--- a/pelican/tools/pelican_import.py
+++ b/pelican/tools/pelican_import.py
@@ -155,7 +155,7 @@ def wp2fields(xml, wp_custpost=False):
                 # Use HTMLParser due to issues with BeautifulSoup 3
                 title = unescape(item.title.contents[0])
             except IndexError:
-                title = "No title [%s]" % item.find("post_name").string
+                title = "No title [{}]".format(item.find("post_name").string)
                 logger.warning('Post "%s" is lacking a proper title', title)
 
             post_name = item.find("post_name").string
@@ -510,11 +510,10 @@ def tumblr2fields(api_key, blogname):
                 title = post.get("question")
                 content = (
                     "<p>"
-                    '<a href="%s" rel="external nofollow">%s</a>'
-                    ": %s"
+                    '<a href="{}" rel="external nofollow">{}</a>'
+                    ": {}"
                     "</p>\n"
-                    " %s"
-                    % (
+                    " {}".format(
                         post.get("asking_name"),
                         post.get("asking_url"),
                         post.get("question"),
@@ -710,19 +709,19 @@ def build_header(
 
     header = "{}\n{}\n".format(title, "#" * column_width(title))
     if date:
-        header += ":date: %s\n" % date
+        header += f":date: {date}\n"
     if author:
-        header += ":author: %s\n" % author
+        header += f":author: {author}\n"
     if categories:
-        header += ":category: %s\n" % ", ".join(categories)
+        header += ":category: {}\n".format(", ".join(categories))
     if tags:
-        header += ":tags: %s\n" % ", ".join(tags)
+        header += ":tags: {}\n".format(", ".join(tags))
     if slug:
-        header += ":slug: %s\n" % slug
+        header += f":slug: {slug}\n"
     if status:
-        header += ":status: %s\n" % status
+        header += f":status: {status}\n"
     if attachments:
-        header += ":attachments: %s\n" % ", ".join(attachments)
+        header += ":attachments: {}\n".format(", ".join(attachments))
     header += "\n"
     return header
 
@@ -732,21 +731,21 @@ def build_asciidoc_header(
 ):
     """Build a header from a list of fields"""
 
-    header = "= %s\n" % title
+    header = f"= {title}\n"
     if author:
-        header += "%s\n" % author
+        header += f"{author}\n"
         if date:
-            header += "%s\n" % date
+            header += f"{date}\n"
     if categories:
-        header += ":category: %s\n" % ", ".join(categories)
+        header += ":category: {}\n".format(", ".join(categories))
     if tags:
-        header += ":tags: %s\n" % ", ".join(tags)
+        header += ":tags: {}\n".format(", ".join(tags))
     if slug:
-        header += ":slug: %s\n" % slug
+        header += f":slug: {slug}\n"
     if status:
-        header += ":status: %s\n" % status
+        header += f":status: {status}\n"
     if attachments:
-        header += ":attachments: %s\n" % ", ".join(attachments)
+        header += ":attachments: {}\n".format(", ".join(attachments))
     header += "\n"
     return header
 
@@ -755,21 +754,21 @@ def build_markdown_header(
     title, date, author, categories, tags, slug, status=None, attachments=None
 ):
     """Build a header from a list of fields"""
-    header = "Title: %s\n" % title
+    header = f"Title: {title}\n"
     if date:
-        header += "Date: %s\n" % date
+        header += f"Date: {date}\n"
     if author:
-        header += "Author: %s\n" % author
+        header += f"Author: {author}\n"
     if categories:
-        header += "Category: %s\n" % ", ".join(categories)
+        header += "Category: {}\n".format(", ".join(categories))
     if tags:
-        header += "Tags: %s\n" % ", ".join(tags)
+        header += "Tags: {}\n".format(", ".join(tags))
     if slug:
-        header += "Slug: %s\n" % slug
+        header += f"Slug: {slug}\n"
     if status:
-        header += "Status: %s\n" % status
+        header += f"Status: {status}\n"
     if attachments:
-        header += "Attachments: %s\n" % ", ".join(attachments)
+        header += "Attachments: {}\n".format(", ".join(attachments))
     header += "\n"
     return header
 
@@ -1076,7 +1075,7 @@ def fields2pelican(
                         error = "Please, check your Pandoc installation."
                         sys.exit(error)
                 except OSError as e:
-                    error = "Pandoc execution failed: %s" % e
+                    error = f"Pandoc execution failed: {e}"
                     sys.exit(error)
 
             with open(out_filename, encoding="utf-8") as fs:
diff --git a/pelican/tools/pelican_quickstart.py b/pelican/tools/pelican_quickstart.py
index 9be107d08..e278e3bc4 100755
--- a/pelican/tools/pelican_quickstart.py
+++ b/pelican/tools/pelican_quickstart.py
@@ -220,7 +220,7 @@ def main():
         CONF["basedir"] = open(project).read().rstrip("\n")
         print(
             "Using project associated with current virtual environment. "
-            "Will save to:\n%s\n" % CONF["basedir"]
+            "Will save to:\n{}\n".format(CONF["basedir"])
         )
     else:
         CONF["basedir"] = os.path.abspath(
@@ -394,7 +394,7 @@ def main():
         render_jinja_template("tasks.py.jinja2", CONF, "tasks.py")
         render_jinja_template("Makefile.jinja2", CONF, "Makefile")
 
-    print("Done. Your new project is available at %s" % CONF["basedir"])
+    print("Done. Your new project is available at {}".format(CONF["basedir"]))
 
 
 if __name__ == "__main__":
diff --git a/pelican/utils.py b/pelican/utils.py
index 6dc4825e0..a29fdf815 100644
--- a/pelican/utils.py
+++ b/pelican/utils.py
@@ -626,7 +626,7 @@ def truncate_html_words(s: str, num: int, end_text: str = "…") -> str:
         out += " " + end_text
     # Close any tags still open
     for tag in truncator.open_tags:
-        out += "</%s>" % tag
+        out += f"</{tag}>"
     # Return string
     return out
 
diff --git a/pelican/writers.py b/pelican/writers.py
index 91b1caebe..1a2cf7b04 100644
--- a/pelican/writers.py
+++ b/pelican/writers.py
@@ -107,14 +107,14 @@ def _open_w(self, filename, encoding, override=False):
         """
         if filename in self._overridden_files:
             if override:
-                raise RuntimeError("File %s is set to be overridden twice" % filename)
+                raise RuntimeError(f"File {filename} is set to be overridden twice")
             logger.info("Skipping %s", filename)
             filename = os.devnull
         elif filename in self._written_files:
             if override:
                 logger.info("Overwriting %s", filename)
             else:
-                raise RuntimeError("File %s is to be overwritten" % filename)
+                raise RuntimeError(f"File {filename} is to be overwritten")
         if override:
             self._overridden_files.add(filename)
         self._written_files.add(filename)
@@ -272,10 +272,10 @@ def _get_localcontext(context, name, kwargs, relative_urls):
                     )
                     paginated_kwargs.update(
                         {
-                            "%s_paginator" % key: paginator,
-                            "%s_page" % key: page,
-                            "%s_previous_page" % key: previous_page,
-                            "%s_next_page" % key: next_page,
+                            f"{key}_paginator": paginator,
+                            f"{key}_page": page,
+                            f"{key}_previous_page": previous_page,
+                            f"{key}_next_page": next_page,
                         }
                     )
 
diff --git a/pyproject.toml b/pyproject.toml
index ccd75f9f2..dd256a44b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -190,7 +190,6 @@ ignore = [
     #  either by removing them from the `select` or `extend-select` configuration,
     #  or adding them to the `ignore` configuration."
     "ISC001",  # single-line-implicit-string-concatenation
-    "UP031",  # printf-string-formatting
     # PERF203 has minimal performance impact, and you have to catch the exception
     # inside the loop if you want to ignore it, so let's ignore PERF203.
     "PERF203",  # try-except-in-loop