diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 1ff65660003..d20e5d78d5f 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,7 +24,7 @@ repos:
           - types-filelock==3.2.7
           - types-requests==2.33.0.20260712
           - types-tabulate==0.10.0.20260508
-          - types-python-dateutil==2.9.0.20260716
+          - types-python-dateutil==2.9.0.20260807
           - scipy-stubs==1.17.1.5
           - SQLAlchemy==2.0.51
         # stages: [push]
diff --git a/build_helpers/schema.json b/build_helpers/schema.json
index 11f6a6727bb..bc1985b17e5 100644
--- a/build_helpers/schema.json
+++ b/build_helpers/schema.json
@@ -1275,34 +1275,55 @@
         },
         "key": {
           "description": "API key for the exchange. Recommended to be set via environment variable FREQTRADE__EXCHANGE__KEY",
-          "type": "string",
-          "default": ""
+          "type": [
+            "string",
+            "null"
+          ],
+          "default": null
         },
         "secret": {
           "description": "API secret for the exchange. Recommended to be set via environment variable FREQTRADE__EXCHANGE__SECRET",
-          "type": "string",
-          "default": ""
+          "type": [
+            "string",
+            "null"
+          ],
+          "default": null
         },
         "password": {
           "description": "Password for the exchange, if required. Recommended to be set via environment variable FREQTRADE__EXCHANGE__PASSWORD",
-          "type": "string",
-          "default": ""
+          "type": [
+            "string",
+            "null"
+          ],
+          "default": null
         },
         "uid": {
           "description": "User ID for the exchange, if required. Recommended to be set via environment variable FREQTRADE__EXCHANGE__UID",
-          "type": "string"
+          "type": [
+            "string",
+            "null"
+          ]
         },
         "account_id": {
           "description": "Account ID for the exchange, if required. Recommended to be set via environment variable FREQTRADE__EXCHANGE__ACCOUNT_ID",
-          "type": "string"
+          "type": [
+            "string",
+            "null"
+          ]
         },
         "wallet_address": {
           "description": "Wallet address for the exchange, if required. Usually used by DEX exchanges. Recommended to be set via environment variable FREQTRADE__EXCHANGE__WALLET_ADDRESS",
-          "type": "string"
+          "type": [
+            "string",
+            "null"
+          ]
         },
         "private_key": {
           "description": "Private key for the exchange, if required. Usually used by DEX exchanges. Recommended to be set via environment variable FREQTRADE__EXCHANGE__PRIVATE_KEY",
-          "type": "string"
+          "type": [
+            "string",
+            "null"
+          ]
         },
         "pair_whitelist": {
           "description": "List of whitelisted trading pairs.",
diff --git a/freqtrade/config_schema/config_schema.py b/freqtrade/config_schema/config_schema.py
index 2e0903f4f9e..aaee625d302 100644
--- a/freqtrade/config_schema/config_schema.py
+++ b/freqtrade/config_schema/config_schema.py
@@ -940,37 +940,37 @@
                     "description": (
                         f"API key for the exchange. {__VIA_ENV} FREQTRADE__EXCHANGE__KEY"
                     ),
-                    "type": "string",
-                    "default": "",
+                    "type": ["string", "null"],
+                    "default": None,
                 },
                 "secret": {
                     "description": (
                         f"API secret for the exchange. {__VIA_ENV} FREQTRADE__EXCHANGE__SECRET"
                     ),
-                    "type": "string",
-                    "default": "",
+                    "type": ["string", "null"],
+                    "default": None,
                 },
                 "password": {
                     "description": (
                         "Password for the exchange, if required. "
                         f"{__VIA_ENV} FREQTRADE__EXCHANGE__PASSWORD"
                     ),
-                    "type": "string",
-                    "default": "",
+                    "type": ["string", "null"],
+                    "default": None,
                 },
                 "uid": {
                     "description": (
                         "User ID for the exchange, if required. "
                         f"{__VIA_ENV} FREQTRADE__EXCHANGE__UID"
                     ),
-                    "type": "string",
+                    "type": ["string", "null"],
                 },
                 "account_id": {
                     "description": (
                         "Account ID for the exchange, if required. "
                         f"{__VIA_ENV} FREQTRADE__EXCHANGE__ACCOUNT_ID"
                     ),
-                    "type": "string",
+                    "type": ["string", "null"],
                 },
                 "wallet_address": {
                     "description": (
@@ -978,14 +978,14 @@
                         "Usually used by DEX exchanges. "
                         f"{__VIA_ENV} FREQTRADE__EXCHANGE__WALLET_ADDRESS"
                     ),
-                    "type": "string",
+                    "type": ["string", "null"],
                 },
                 "private_key": {
                     "description": (
                         "Private key for the exchange, if required. Usually used by DEX exchanges. "
                         f"{__VIA_ENV} FREQTRADE__EXCHANGE__PRIVATE_KEY"
                     ),
-                    "type": "string",
+                    "type": ["string", "null"],
                 },
                 "pair_whitelist": {
                     "description": "List of whitelisted trading pairs.",
diff --git a/freqtrade/configuration/config_secrets.py b/freqtrade/configuration/config_secrets.py
index 797caba2342..c36042c3b25 100644
--- a/freqtrade/configuration/config_secrets.py
+++ b/freqtrade/configuration/config_secrets.py
@@ -64,4 +64,4 @@ def remove_exchange_credentials(exchange_config: ExchangeConfig, dry_run: bool)
         if "." in key:
             key1 = key.removeprefix("exchange.")
             if key1 in exchange_config:
-                exchange_config[key1] = ""
+                exchange_config[key1] = None
diff --git a/freqtrade/constants.py b/freqtrade/constants.py
index e86dde00d7d..dafbd411e6b 100644
--- a/freqtrade/constants.py
+++ b/freqtrade/constants.py
@@ -196,8 +196,8 @@
     "dry_run": True,
     "exchange": {
         "name": "",
-        "key": "",
-        "secret": "",
+        "key": None,
+        "secret": None,
         "pair_whitelist": [],
         "ccxt_async_config": {},
     },
diff --git a/freqtrade/exchange/exchange.py b/freqtrade/exchange/exchange.py
index ff66c230ebd..b33690a168e 100644
--- a/freqtrade/exchange/exchange.py
+++ b/freqtrade/exchange/exchange.py
@@ -399,8 +399,8 @@ def _init_ccxt(
             ),
             "secret": exchange_config.get("secret"),
             "password": exchange_config.get("password"),
-            "uid": exchange_config.get("uid", ""),
-            "accountId": exchange_config.get("account_id", exchange_config.get("accountId", "")),
+            "uid": exchange_config.get("uid"),
+            "accountId": exchange_config.get("account_id", exchange_config.get("accountId")),
             # DEX attributes:
             "walletAddress": exchange_config.get(
                 "wallet_address", exchange_config.get("walletAddress")
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 4d7aaea9b8e..89275346e0c 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -6,7 +6,7 @@
 -r requirements-freqai-rl.txt
 -r docs/requirements-docs.txt
 
-ruff==0.16.1
+ruff==0.16.2
 mypy==2.3.0
 pre-commit==4.6.1
 pytest==9.1.1
@@ -17,7 +17,7 @@ pytest-random-order==1.2.0
 pytest-timeout==2.4.0
 pytest-xdist==3.8.0
 # For datetime mocking
-time-machine==3.3.0
+time-machine==3.3.1
 
 # Convert jupyter notebooks to markdown documents
 nbconvert==7.17.1
@@ -28,7 +28,7 @@ types-cachetools==7.0.0.20260713
 types-filelock==3.2.7
 types-requests==2.33.0.20260712
 types-tabulate==0.10.0.20260508
-types-python-dateutil==2.9.0.20260716
+types-python-dateutil==2.9.0.20260807
 pip-audit==2.10.1
 # For build step in CI
 build==1.5.0
diff --git a/requirements.txt b/requirements.txt
index 7347549a988..2785f62ff85 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,7 +8,7 @@ ft-pandas-ta==0.3.16
 ta-lib==0.7.1
 technical==1.7.0
 
-ccxt==4.5.71
+ccxt==4.5.73
 cryptography==50.0.0
 aiohttp==3.14.3
 SQLAlchemy==2.0.51
@@ -60,4 +60,4 @@ websockets==17.0.1
 janus==2.0.0
 
 ast-comments==1.3.0
-packaging==26.2
+packaging==26.3
diff --git a/tests/exchange_online/conftest.py b/tests/exchange_online/conftest.py
index 623da685f40..08ff88ac201 100644
--- a/tests/exchange_online/conftest.py
+++ b/tests/exchange_online/conftest.py
@@ -773,8 +773,8 @@ class TestExchangeOnlineSetup(TypedDict):
 def exchange_conf():
     config = get_default_conf_usdt((Path(__file__).parent / "testdata").resolve())
     config["exchange"]["pair_whitelist"] = []
-    config["exchange"]["key"] = ""
-    config["exchange"]["secret"] = ""
+    config["exchange"]["apiKey"] = None
+    config["exchange"]["secret"] = None
     config["dry_run"] = False
     config["entry_pricing"]["use_order_book"] = True
     config["exit_pricing"]["use_order_book"] = True
diff --git a/tests/freqtradebot/test_freqtradebot.py b/tests/freqtradebot/test_freqtradebot.py
index 0fdfdbb74ad..0176c33ac59 100644
--- a/tests/freqtradebot/test_freqtradebot.py
+++ b/tests/freqtradebot/test_freqtradebot.py
@@ -188,16 +188,16 @@ def test_load_strategy_no_keys(default_conf_usdt, mocker, runmode, caplog) -> No
     strategy_config = freqtrade.strategy.config
     assert id(strategy_config["exchange"]) == id(conf["exchange"])
     # Keys have been removed and are not passed to the exchange
-    assert strategy_config["exchange"]["key"] == ""
-    assert strategy_config["exchange"]["secret"] == ""
+    assert strategy_config["exchange"]["key"] is None
+    assert strategy_config["exchange"]["secret"] is None
 
     assert erm.call_count == 1
     ex_conf = erm.call_args_list[0][1]["exchange_config"]
     assert id(ex_conf) != id(conf["exchange"])
     # Keys are still present
-    assert ex_conf["key"] != ""
+    assert ex_conf["key"] is not None
     assert ex_conf["key"] == default_conf_usdt["exchange"]["key"]
-    assert ex_conf["secret"] != ""
+    assert ex_conf["secret"] is not None
     assert ex_conf["secret"] == default_conf_usdt["exchange"]["secret"]
 
 
diff --git a/tests/test_configuration.py b/tests/test_configuration.py
index e58a7176aa5..dc8e1974dc9 100644
--- a/tests/test_configuration.py
+++ b/tests/test_configuration.py
@@ -1118,9 +1118,9 @@ def test_load_config_stoploss_exchange_limit_ratio(all_conf) -> None:
 @pytest.mark.parametrize(
     "keys",
     [
-        ("exchange", "key", ""),
-        ("exchange", "secret", ""),
-        ("exchange", "password", ""),
+        ("exchange", "key", None),
+        ("exchange", "secret", None),
+        ("exchange", "password", None),
     ],
 )
 def test_load_config_default_subkeys(all_conf, keys) -> None:
@@ -1613,11 +1613,11 @@ def test_remove_exchange_credentials(default_conf) -> None:
     conf = deepcopy(default_conf)
     remove_exchange_credentials(conf["exchange"], False)
 
-    assert conf["exchange"]["key"] != ""
-    assert conf["exchange"]["secret"] != ""
+    assert conf["exchange"]["key"] is not None
+    assert conf["exchange"]["secret"] is not None
 
     remove_exchange_credentials(conf["exchange"], True)
-    assert conf["exchange"]["key"] == ""
-    assert conf["exchange"]["secret"] == ""
-    assert conf["exchange"].get("password", "") == ""
-    assert conf["exchange"].get("uid", "") == ""
+    assert conf["exchange"]["key"] is None
+    assert conf["exchange"]["secret"] is None
+    assert conf["exchange"].get("password") is None
+    assert conf["exchange"].get("uid") is None