Last Updated: 3/11/2026

Testing

Testing Hono applications is straightforward. Create requests, pass them to your app, and validate responses.

Basic Testing

Use app.request() to test your routes:


import { describe, test, expect } from 'vitest'
import { Hono } from 'hono'
 
const app = new Hono()
 
app.get('/posts', (c) => {
  return c.text('Many posts')
})
 
describe('Example', () => {
  test('GET /posts', async () => {
    const res = await app.request('/posts')
    expect(res.status).toBe(200)
    expect(await res.text()).toBe('Many posts')
  })
})

Testing POST Requests

Simple POST


app.post('/posts', (c) => {
  return c.json({ message: 'Created' }, 201, {
    'X-Custom': 'Thank you',
  })
})
 
test('POST /posts', async () => {
  const res = await app.request('/posts', {
    method: 'POST',
  })
  expect(res.status).toBe(201)
  expect(res.headers.get('X-Custom')).toBe('Thank you')
  expect(await res.json()).toEqual({ message: 'Created' })
})

POST with JSON


test('POST /posts with JSON', async () => {
  const res = await app.request('/posts', {
    method: 'POST',
    body: JSON.stringify({ message: 'hello hono' }),
    headers: new Headers({ 'Content-Type': 'application/json' }),
  })
  expect(res.status).toBe(201)
  expect(await res.json()).toEqual({ message: 'Created' })
})

POST with Form Data


test('POST /posts with form data', async () => {
  const formData = new FormData()
  formData.append('message', 'hello')
  
  const res = await app.request('/posts', {
    method: 'POST',
    body: formData,
  })
  expect(res.status).toBe(201)
})

Using Request Objects

Pass a Request instance directly:


test('POST /posts with Request', async () => {
  const req = new Request('http://localhost/posts', {
    method: 'POST',
  })
  const res = await app.request(req)
  expect(res.status).toBe(201)
})

Testing with Environment Variables

Pass environment variables as the third parameter:


const MOCK_ENV = {
  API_HOST: 'example.com',
  DB: {
    prepare: () => {
      /* mocked D1 */
    },
  },
}
 
test('GET /posts', async () => {
  const res = await app.request('/posts', {}, MOCK_ENV)
  expect(res.status).toBe(200)
})

Testing Middleware

Test middleware behavior:


import { basicAuth } from 'hono/basic-auth'
 
const app = new Hono()
 
app.use(
  '/admin/*',
  basicAuth({
    username: 'admin',
    password: 'secret',
  })
)
 
app.get('/admin', (c) => c.text('Admin panel'))
 
test('Unauthorized access', async () => {
  const res = await app.request('/admin')
  expect(res.status).toBe(401)
})
 
test('Authorized access', async () => {
  const res = await app.request('/admin', {
    headers: {
      Authorization: 'Basic ' + btoa('admin:secret'),
    },
  })
  expect(res.status).toBe(200)
  expect(await res.text()).toBe('Admin panel')
})

Runtime-Specific Testing

Cloudflare Workers

Use @cloudflare/vitest-pool-workers:


npm install -D @cloudflare/vitest-pool-workers

See Cloudflare’s Vitest integration guide .

Deno

Use Deno’s built-in test runner:


import { assertEquals } from '@std/assert'
import { Hono } from 'hono'
 
Deno.test('GET /posts', async () => {
  const app = new Hono()
  app.get('/posts', (c) => c.text('Many posts'))
 
  const res = await app.request('http://localhost/posts')
  assertEquals(res.status, 200)
  assertEquals(await res.text(), 'Many posts')
})

Bun

Use bun:test:


import { describe, expect, it } from 'bun:test'
import { Hono } from 'hono'
 
const app = new Hono()
app.get('/posts', (c) => c.text('Many posts'))
 
describe('API tests', () => {
  it('Should return posts', async () => {
    const res = await app.request('/posts')
    expect(res.status).toBe(200)
    expect(await res.text()).toBe('Many posts')
  })
})

Testing Helper

For type-safe testing, use the testing helper:


import { testClient } from 'hono/testing'
 
const client = testClient(app)
 
const res = await client.posts.$get()
expect(res.status).toBe(200)

Next Steps

Explore Helpers and Built-in Middleware for more features.