diff --git a/meilisearch-core/src/serde/convert_to_number.rs b/meilisearch-core/src/serde/convert_to_number.rs
deleted file mode 100644
index a67e01692..000000000
--- a/meilisearch-core/src/serde/convert_to_number.rs
+++ /dev/null
@@ -1,198 +0,0 @@
-use std::str::FromStr;
-
-use ordered_float::OrderedFloat;
-use serde::ser;
-use serde::Serialize;
-
-use super::SerializerError;
-use crate::Number;
-
-pub struct ConvertToNumber;
-
-impl ser::Serializer for ConvertToNumber {
-    type Ok = Number;
-    type Error = SerializerError;
-    type SerializeSeq = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeTuple = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeTupleStruct = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeTupleVariant = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeMap = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeStruct = ser::Impossible<Self::Ok, Self::Error>;
-    type SerializeStructVariant = ser::Impossible<Self::Ok, Self::Error>;
-
-    fn serialize_bool(self, value: bool) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Unsigned(u64::from(value)))
-    }
-
-    fn serialize_char(self, _value: char) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "char" })
-    }
-
-    fn serialize_i8(self, value: i8) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Signed(i64::from(value)))
-    }
-
-    fn serialize_i16(self, value: i16) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Signed(i64::from(value)))
-    }
-
-    fn serialize_i32(self, value: i32) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Signed(i64::from(value)))
-    }
-
-    fn serialize_i64(self, value: i64) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Signed(value))
-    }
-
-    fn serialize_u8(self, value: u8) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Unsigned(u64::from(value)))
-    }
-
-    fn serialize_u16(self, value: u16) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Unsigned(u64::from(value)))
-    }
-
-    fn serialize_u32(self, value: u32) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Unsigned(u64::from(value)))
-    }
-
-    fn serialize_u64(self, value: u64) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Unsigned(value))
-    }
-
-    fn serialize_f32(self, value: f32) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Float(OrderedFloat(f64::from(value))))
-    }
-
-    fn serialize_f64(self, value: f64) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::Float(OrderedFloat(value)))
-    }
-
-    fn serialize_str(self, value: &str) -> Result<Self::Ok, Self::Error> {
-        Ok(Number::from_str(value)?)
-    }
-
-    fn serialize_bytes(self, _v: &[u8]) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "&[u8]" })
-    }
-
-    fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "Option",
-        })
-    }
-
-    fn serialize_some<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
-    where
-        T: Serialize,
-    {
-        Err(SerializerError::UnrankableType {
-            type_name: "Option",
-        })
-    }
-
-    fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "()" })
-    }
-
-    fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "unit struct",
-        })
-    }
-
-    fn serialize_unit_variant(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-    ) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "unit variant",
-        })
-    }
-
-    fn serialize_newtype_struct<T: ?Sized>(
-        self,
-        _name: &'static str,
-        value: &T,
-    ) -> Result<Self::Ok, Self::Error>
-    where
-        T: Serialize,
-    {
-        value.serialize(self)
-    }
-
-    fn serialize_newtype_variant<T: ?Sized>(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-        _value: &T,
-    ) -> Result<Self::Ok, Self::Error>
-    where
-        T: Serialize,
-    {
-        Err(SerializerError::UnrankableType {
-            type_name: "newtype variant",
-        })
-    }
-
-    fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "sequence",
-        })
-    }
-
-    fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "tuple" })
-    }
-
-    fn serialize_tuple_struct(
-        self,
-        _name: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "tuple struct",
-        })
-    }
-
-    fn serialize_tuple_variant(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "tuple variant",
-        })
-    }
-
-    fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "map" })
-    }
-
-    fn serialize_struct(
-        self,
-        _name: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeStruct, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "struct",
-        })
-    }
-
-    fn serialize_struct_variant(
-        self,
-        _name: &'static str,
-        _variant_index: u32,
-        _variant: &'static str,
-        _len: usize,
-    ) -> Result<Self::SerializeStructVariant, Self::Error> {
-        Err(SerializerError::UnrankableType {
-            type_name: "struct variant",
-        })
-    }
-}
diff --git a/meilisearch-core/src/serde/mod.rs b/meilisearch-core/src/serde/mod.rs
index 6a1e51a09..50e18687e 100644
--- a/meilisearch-core/src/serde/mod.rs
+++ b/meilisearch-core/src/serde/mod.rs
@@ -8,12 +8,10 @@ macro_rules! forward_to_unserializable_type {
     }
 }
 
-mod convert_to_number;
 mod convert_to_string;
 mod deserializer;
 mod extract_document_id;
 
-pub use self::convert_to_number::ConvertToNumber;
 pub use self::convert_to_string::ConvertToString;
 pub use self::deserializer::{Deserializer, DeserializerError};
 pub use self::extract_document_id::{compute_document_id, extract_document_id, value_to_string};
diff --git a/meilisearch-core/src/update/documents_addition.rs b/meilisearch-core/src/update/documents_addition.rs
index b7e6395af..ddb3c8340 100644
--- a/meilisearch-core/src/update/documents_addition.rs
+++ b/meilisearch-core/src/update/documents_addition.rs
@@ -1,11 +1,10 @@
 use std::collections::HashMap;
 use std::fmt::Write as _;
-use std::fmt;
 
 use fst::{set::OpBuilder, SetBuilder};
 use indexmap::IndexMap;
 use sdset::{duo::Union, SetOperation};
-use serde::{Deserialize, Serialize};
+use serde::Deserialize;
 use serde_json::Value;
 
 use meilisearch_types::DocumentId;
@@ -16,10 +15,9 @@ use crate::database::{UpdateEvent, UpdateEventsEmitter};
 use crate::facets;
 use crate::raw_indexer::RawIndexer;
 use crate::serde::{extract_document_id, Deserializer};
-use crate::serde::ConvertToNumber;
 use crate::store;
 use crate::update::{apply_documents_deletion, compute_short_prefixes, next_update_id, Update};
-use crate::{Error, MResult, RankedMap};
+use crate::{Error, Number, MResult, RankedMap};
 
 pub struct DocumentsAddition<D> {
     updates_store: store::Updates,
@@ -174,6 +172,20 @@ fn index_value(
     }
 }
 
+// TODO move this helper functions elsewhere
+fn value_to_number(value: &Value) -> Option<Number> {
+    use std::str::FromStr;
+
+    match value {
+        Value::Null => None,
+        Value::Bool(boolean) => Some(Number::Unsigned(*boolean as u64)),
+        Value::Number(number) => Number::from_str(&number.to_string()).ok(), // TODO improve that
+        Value::String(string) => Number::from_str(string).ok(),
+        Value::Array(_array) => None,
+        Value::Object(_object) => None,
+    }
+}
+
 pub fn apply_addition<'a, 'b>(
     writer: &'a mut heed::RwTxn<'b, MainT>,
     index: &store::Index,
@@ -263,7 +275,7 @@ pub fn apply_addition<'a, 'b>(
             }
 
             if schema.is_ranked(field_id) {
-                let number = value.serialize(ConvertToNumber).unwrap_or_default();
+                let number = value_to_number(&value).unwrap_or_default();
                 ranked_map.insert(document_id, field_id, number);
             }
         }
@@ -360,7 +372,7 @@ pub fn reindex_all_documents(writer: &mut heed::RwTxn<MainT>, index: &store::Ind
             }
 
             if schema.is_ranked(field_id) {
-                let number = value.serialize(ConvertToNumber).unwrap_or_default();
+                let number = value_to_number(&value).unwrap_or_default();
                 ranked_map.insert(document_id, field_id, number);
             }
         }