diff --git a/README.md b/README.md
index 331be9a..edb6335 100644
--- a/README.md
+++ b/README.md
@@ -140,7 +140,7 @@ You can specify configuration options either via a config file (default: `config
 | `app.aggregation_time` /<br>`WAKAPI_AGGREGATION_TIME`                        | `0 15 2 * * *`                                   | Time of day at which to periodically run summary generation for all users                                                                                                |
 | `app.report_time_weekly` /<br>`WAKAPI_REPORT_TIME_WEEKLY`                    | `0 0 18 * * 5`                                   | Week day and time at which to send e-mail reports                                                                                                                        |
 | `app.leaderboard_generation_time` /<br>`WAKAPI_LEADERBOARD_GENERATION_TIME`  | `0 0 6 * * *,0 0 18 * * *`                       | One or multiple times of day at which to re-calculate the leaderboard                                                                                                    |
-| `app.data_cleanup_time` /<br>`WAKAPI_DATA_CLEANUP_TIME`                      | `0 0 6 * * 7`                                    | When to perform data cleanup operations (see `app.data_retention_months`)                                                                                                |
+| `app.data_cleanup_time` /<br>`WAKAPI_DATA_CLEANUP_TIME`                      | `0 0 6 * * 0`                                    | When to perform data cleanup operations (see `app.data_retention_months`)                                                                                                |
 | `app.import_batch_size` /<br>`WAKAPI_IMPORT_BATCH_SIZE`                      | `50`                                             | Size of batches of heartbeats to insert to the database during importing from external services                                                                          |
 | `app.inactive_days` /<br>`WAKAPI_INACTIVE_DAYS`                              | `7`                                              | Number of days after which to consider a user inactive (only for metrics)                                                                                                |
 | `app.heartbeat_max_age /`<br>`WAKAPI_HEARTBEAT_MAX_AGE`                      | `4320h`                                          | Maximum acceptable age of a heartbeat (see [`ParseDuration`](https://pkg.go.dev/time#ParseDuration))                                                                     |
diff --git a/config.default.yml b/config.default.yml
index e380130..3d3041d 100644
--- a/config.default.yml
+++ b/config.default.yml
@@ -18,7 +18,7 @@ app:
   aggregation_time: '0 15 2 * * *'                          # time at which to run daily aggregation batch jobs
   leaderboard_generation_time: '0 0 6 * * *,0 0 18 * * *'   # times at which to re-calculate the leaderboard
   report_time_weekly: '0 0 18 * * 5'                        # time at which to fan out weekly reports (extended cron)
-  data_cleanup_time: '0 0 6 * * 7'                          # time at which to run old data cleanup (if enabled through data_retention_months)
+  data_cleanup_time: '0 0 6 * * 0'                          # time at which to run old data cleanup (if enabled through data_retention_months)
   inactive_days: 7                                          # time of previous days within a user must have logged in to be considered active
   import_batch_size: 50                                     # maximum number of heartbeats to insert into the database within one transaction
   heartbeat_max_age: '4320h'                                # maximum acceptable age of a heartbeat (see https://pkg.go.dev/time#ParseDuration)
diff --git a/config/config.go b/config/config.go
index 8b27ae0..86600cb 100644
--- a/config/config.go
+++ b/config/config.go
@@ -72,7 +72,7 @@ type appConfig struct {
 	AggregationTime           string                       `yaml:"aggregation_time" default:"0 15 2 * * *" env:"WAKAPI_AGGREGATION_TIME"`
 	LeaderboardGenerationTime string                       `yaml:"leaderboard_generation_time" default:"0 0 6 * * *,0 0 18 * * *" env:"WAKAPI_LEADERBOARD_GENERATION_TIME"`
 	ReportTimeWeekly          string                       `yaml:"report_time_weekly" default:"0 0 18 * * 5" env:"WAKAPI_REPORT_TIME_WEEKLY"`
-	DataCleanupTime           string                       `yaml:"data_cleanup_time" default:"0 0 6 * * 7" env:"WAKAPI_DATA_CLEANUP_TIME"`
+	DataCleanupTime           string                       `yaml:"data_cleanup_time" default:"0 0 6 * * 0" env:"WAKAPI_DATA_CLEANUP_TIME"`
 	ImportBackoffMin          int                          `yaml:"import_backoff_min" default:"5" env:"WAKAPI_IMPORT_BACKOFF_MIN"`
 	ImportBatchSize           int                          `yaml:"import_batch_size" default:"50" env:"WAKAPI_IMPORT_BATCH_SIZE"`
 	InactiveDays              int                          `yaml:"inactive_days" default:"7" env:"WAKAPI_INACTIVE_DAYS"`