How to post query parameters with Axios?

axios signature for post is axios.post(url[, data[, config]]). So you want to send params object within the third argument:

.post(`/mails/users/sendVerificationMail`, null, { params: {  mail,  firstname}}).then(response => response.status).catch(err => console.warn(err));

This will POST an empty body with the two query params:

POST http://localhost:8000/api/mails/users/sendVerificationMail?mail=lol%40lol.com&firstname=myFirstName

As of 2021 insted of null i had to add {} in order to make it work!

axios.post(        url,        {},        {          params: {            key,            checksum          }        }      )      .then(response => {        return success(response);      })      .catch(error => {        return fail(error);      });

In my case, the API responded with a CORS error. I instead formatted the query parameters into query string. It successfully posted data and also avoided the CORS issue.

        var data = {};        const params = new URLSearchParams({          contact: this.ContactPerson,          phoneNumber: this.PhoneNumber,          email: this.Email        }).toString();        const url =          "https://test.com/api/UpdateProfile?" +          params;        axios          .post(url, data, {            headers: {              aaid: this.ID,              token: this.Token            }          })          .then(res => {            this.Info = JSON.parse(res.data);          })          .catch(err => {            console.log(err);          });