diff --git a/src/lib.rs b/src/lib.rs
index 8c53513..8c2f753 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,6 +5,7 @@ pub mod models;
 pub mod os;
 pub mod parsing;
 pub mod table;
+pub mod utils_calc;
 
 pub use holiday::Hollidays;
 
diff --git a/src/main.rs b/src/main.rs
index 4e128bf..644ddfc 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,12 +1,13 @@
 use clap::Parser as _;
 use ecb_rates::cache::{Cache, CacheLine};
 use reqwest::{Client, IntoUrl};
-use std::{borrow::BorrowMut, collections::HashMap, process::ExitCode};
+use std::process::ExitCode;
 
 use ecb_rates::cli::{Cli, FormatOption};
 use ecb_rates::models::ExchangeRateResult;
 use ecb_rates::parsing::parse;
 use ecb_rates::table::{TableRef, TableTrait as _};
+use ecb_rates::utils_calc::filter_currencies;
 
 async fn get_and_parse(url: impl IntoUrl) -> anyhow::Result<Vec<ExchangeRateResult>> {
     let client = Client::new();
@@ -14,24 +15,6 @@ async fn get_and_parse(url: impl IntoUrl) -> anyhow::Result<Vec<ExchangeRateResu
     parse(&xml_content)
 }
 
-fn filter_currencies(exchange_rate_results: &mut [ExchangeRateResult], currencies: &[String]) {
-    for exchange_rate in exchange_rate_results {
-        let rates_ptr: *mut HashMap<String, f64> = &mut exchange_rate.rates;
-        exchange_rate
-            .rates
-            .keys()
-            .filter(|x| !currencies.contains(x))
-            .for_each(|key_to_remove| {
-                /* This is safe, since we:
-                 * 1. Already have a mutable reference.
-                 * 2. Don't run the code in paralell
-                 */
-                let rates = unsafe { (*rates_ptr).borrow_mut() };
-                rates.remove_entry(key_to_remove);
-            });
-    }
-}
-
 #[tokio::main(flavor = "current_thread")]
 async fn main() -> ExitCode {
     let cli = Cli::parse();
diff --git a/src/utils_calc.rs b/src/utils_calc.rs
new file mode 100644
index 0000000..f3a21cb
--- /dev/null
+++ b/src/utils_calc.rs
@@ -0,0 +1,21 @@
+use std::{borrow::BorrowMut, collections::HashMap};
+
+use crate::models::ExchangeRateResult;
+
+pub fn filter_currencies(exchange_rate_results: &mut [ExchangeRateResult], currencies: &[String]) {
+    for exchange_rate in exchange_rate_results {
+        let rates_ptr: *mut HashMap<String, f64> = &mut exchange_rate.rates;
+        exchange_rate
+            .rates
+            .keys()
+            .filter(|x| !currencies.contains(x))
+            .for_each(|key_to_remove| {
+                /* This is safe, since we:
+                 * 1. Already have a mutable reference.
+                 * 2. Don't run the code in paralell
+                 */
+                let rates = unsafe { (*rates_ptr).borrow_mut() };
+                rates.remove_entry(key_to_remove);
+            });
+    }
+}