---
title: Logging in
slug: docs/parse-graphql/graphql-login
description: This is a recipe for logging in an existing user in Parse Server backend through the GraphQL API.
image: https://www.back4app.com/images/logo-social.png
docTags:
createdAt: 2024-02-26T19:18:47.038Z
---
# Logging in an existing user through the Parse GraphQL API
# Problem
You want to log in an existing user in your backend through the Parse GraphQL API.
## Solution
Using the Parse GraphQL API, you can log in an existing user just by sending the user’s credentials through the `logIn` mutation. The `username` and `password` arguments are mandatory. The mutation will return back all users’ fields, including the `sessionToken`.
After logging in an existing user, you can use the [authenticating an user](https://www.back4app.com/docs/parse-graphql/graphql-user-authentication) recipe to send the `sessionToken` in the following operations so they will be executed in the behavior of this user. You can also use the [logging out](https://www.back4app.com/docs/parse-graphql/graphql-logout-mutation) recipe to destroy the `sessionToken`.
## Version Information
Depending on the version of Parse you choose to run, the GraphQL queries, mutations and results will be slightly different.
Please choose the correct example along with the Parse version you are running.
## Parse Server 3.10.0 and later
:::CodeblockTabs
Request
```graphql
1 mutation LogIn{
2 logIn(input: {
3 username: "somefolk"
4 password: "somepassword"
5 }){
6 viewer{
7 user{
8 id
9 createdAt
10 updatedAt
11 username
12 }
13 sessionToken
14 }
15 }
16 }
```
Response
```graphql
1 {
2 "data": {
3 "logIn": {
4 "viewer": {
5 "user": {
6 "id": "X1VzZXI6UHNOUkJ3Y1YyRQ==",
7 "createdAt": "2020-02-06T13:38:04.517Z",
8 "updatedAt": "2020-02-06T13:38:04.517Z",
9 "username": "somefolk"
10 },
11 "sessionToken": "r:a5318d28821a78069f5b618de35b57bb"
12 }
13 }
14 }
15 }
```
:::
::::ExpandableHeading
**Parse Server 3.9.0**
:::CodeblockTabs
Request
```graphql
1 mutation LogIn{
2 logIn(fields:{
3 username: "somefolk"
4 password: "somepassword"
5 }){
6 id,
7 createdAt,
8 updatedAt,
9 username,
10 sessionToken
11 }
12 }
```
Response
```graphql
1 {
2 "data": {
3 "viewer": {
4 "sessionToken": "r:1450d329038f876835fb7aac16742380",
5 "username": "somefolk"
6 }
7 }
8 }
```
:::
::::
::::ExpandableHeading
**Parse Server 3.8.0**
:::CodeblockTabs
Request
```graphql
1 mutation LogIn{
2 logIn(fields:{
3 username: "somefolk"
4 password: "somepassword"
5 }){
6 objectId,
7 createdAt,
8 updatedAt,
9 username,
10 sessionToken
11 }
12 }
```
Response
```graphql
1 {
2 "data": {
3 "logIn": {
4 "objectId": "KTznKVzto2",
5 "createdAt": "2019-11-04T14:23:46.014Z",
6 "updatedAt": "2019-11-04T14:23:46.014Z",
7 "username": "somefolk",
8 "sessionToken": "r:fe39d9de406d53d13e9af1efbbe967a8"
9 }
10 }
11 }
```
:::
::::
::::ExpandableHeading
**Parse Server 3.7.2**
:::CodeblockTabs
Request
```graphql
1 mutation LogIn {
2 users {
3 logIn(username: "somefolk", password: "somepassword") {
4 objectId,
5 createdAt,
6 updatedAt,
7 username,
8 sessionToken
9 }
10 }
11 }
```
Response
```graphql
1 {
2 "data": {
3 "users": {
4 "logIn": {
5 "objectId": "NyU1lNlhPd",
6 "createdAt": "2019-07-29T09:09:58.222Z",
7 "updatedAt": "2019-07-29T09:09:58.222Z",
8 "username": "somefolk",
9 "sessionToken": "r:cbca71d29d7601761b48ed01bbe9638d"
10 }
11 }
12 }
13 }
```
:::
::::