diff --git a/api/src/routes/candidate.rs b/api/src/routes/candidate.rs
index 7c7775b..0dcb1ce 100644
--- a/api/src/routes/candidate.rs
+++ b/api/src/routes/candidate.rs
@@ -102,6 +102,7 @@ pub async fn post_details(
 ) -> Result<Json<ApplicationDetails>, Custom<String>> {
     let db = conn.into_inner();
     let form = details.into_inner();
+    form.candidate.validate_self().map_err(to_custom_error)?;
     let application: application::Model = session.into();
     let candidate = ApplicationService::find_related_candidate(&db, &application).await.map_err(to_custom_error)?; // TODO
 
diff --git a/core/src/error.rs b/core/src/error.rs
index ee3ac40..22685ec 100644
--- a/core/src/error.rs
+++ b/core/src/error.rs
@@ -16,6 +16,8 @@ pub enum ServiceError {
     ExpiredSession,
     #[error("Missing details")]
     MissingDetails,
+    #[error("Validation error: {0}")]
+    ValidationError(#[from] validator::ValidationErrors),
     #[error("User already exists")]
     UserAlreadyExists,
     #[error("Candidate not found")]
@@ -85,6 +87,7 @@ impl ServiceError {
             ServiceError::InvalidApplicationId => 400,
             ServiceError::ParentOverflow => 400,
             ServiceError::MissingDetails => 400,
+            ServiceError::ValidationError(_) => 400,
             ServiceError::Unauthorized => 401,
             ServiceError::InvalidCredentials => 401,
             ServiceError::ExpiredSession => 401,
diff --git a/core/src/models/candidate.rs b/core/src/models/candidate.rs
index 5eb16f8..521cade 100644
--- a/core/src/models/candidate.rs
+++ b/core/src/models/candidate.rs
@@ -1,6 +1,7 @@
 use chrono::NaiveDate;
 use entity::{application, candidate};
 use serde::{Deserialize, Serialize};
+use validator::Validate;
 
 use crate::{
     error::ServiceError,
@@ -57,28 +58,47 @@ pub struct CreateCandidateResponse {
     pub password: String,
 }
 
-#[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Eq)]
+#[derive(Debug, Serialize, Deserialize, Validate, Clone, PartialEq, Eq)]
 #[serde(rename_all = "camelCase")]
 pub struct CandidateDetails {
+    #[validate(length(min = 1, max = 255))]
     pub name: String,
+    #[validate(length(min = 1, max = 255))]
     pub surname: String,
+    #[validate(length(min = 1, max = 255))]
     pub birth_surname: String,
+    #[validate(length(min = 1, max = 255))]
     pub birthplace: String,
     pub birthdate: NaiveDate,
+    #[validate(length(min = 1, max = 255))]
     pub address: String,
     pub letter_address: String,
+    #[validate(length(min = 1, max = 31))]
     pub telephone: String,
+    #[validate(length(min = 1, max = 255))]
     pub citizenship: String,
+    #[validate(email)]
     pub email: String,
     pub sex: String,
+    #[validate(length(min = 1, max = 255))]
     pub personal_id_number: String,
+    #[validate(length(min = 1, max = 255))]
     pub school_name: String,
+    #[validate(length(min = 1, max = 255))]
     pub health_insurance: String,
     pub grades: GradeList,
     pub first_school: School,
     pub second_school: School,
     pub test_language: String,
 }
+impl CandidateDetails {
+    pub fn validate_self(&self) -> Result<(), ServiceError> {
+        self.first_school.validate()?;
+        self.second_school.validate()?;
+        self.validate()
+            .map_err(ServiceError::ValidationError)
+    }
+}
 #[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Eq)]
 #[serde(rename_all = "camelCase")]
 pub struct ParentDetails {
diff --git a/core/src/models/candidate_details.rs b/core/src/models/candidate_details.rs
index e3f95b0..836e903 100644
--- a/core/src/models/candidate_details.rs
+++ b/core/src/models/candidate_details.rs
@@ -227,7 +227,6 @@ impl EncryptedCandidateDetails {
         self.personal_id_number.is_some() &&
         self.school_name.is_some() &&
         self.health_insurance.is_some() &&
-        self.grades_json.is_some() &&
         self.first_school.is_some() &&
         self.second_school.is_some()
 
diff --git a/core/src/models/school.rs b/core/src/models/school.rs
index 27c18d6..a04b84d 100644
--- a/core/src/models/school.rs
+++ b/core/src/models/school.rs
@@ -1,8 +1,13 @@
 use serde::{Serialize, Deserialize};
+use validator::Validate;
 
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+use crate::error::ServiceError;
+
+#[derive(Debug, Clone, Serialize, Deserialize, Validate, PartialEq, Eq)]
 pub struct School {
+    #[validate(length(min = 1, max = 255))]
     name: String,
+    #[validate(length(min = 1, max = 255))]
     field: String,
 }
 
@@ -13,6 +18,11 @@ impl School {
         )
     }
 
+    pub fn validate_self(&self) -> Result<(), ServiceError> {
+        self.validate()
+            .map_err(ServiceError::ValidationError)
+    }
+
     pub fn name(&self) -> &str {
         &self.name
     }