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100% Local · Light Postman Client · Fast HTTP requests
API Tester
Lightweight, in-browser REST client. Test HTTP endpoints with custom parameters, headers, bodies, and auth configurations securely.
Encrypted browser sandbox Zero data logging
ParameterValue
Enter a URL and click Send to make a request
Developer Reference
Free Online REST API Client with Multi-Tab Sessions
A lightweight, free, and secure browser-based Postman alternative. Test GET, POST, PUT, and DELETE requests across up to 6 independent tab sessions — complete with auth, parameters, body editors, and instant response inspection. No install. No login.
Multi-Tab Sessions
Up to 6 isolated request tabs — each with its own URL, auth, body, and response.
100% Local
All HTTP calls execute in your browser. Zero server relay. Credentials stay private.
Full Auth Support
Basic Auth (with password reveal), Bearer, JWT, and API Key in header or query.
Rich Response View
Status badges, response time, body size, raw headers, and formatted JSON output.
Multi-Tab API Session Manager
New
The tab bar at the top of the tool works exactly like browser tabs — each pill is an entirely separate request context. Open a GET in one tab, a POST in another, and a Bearer-authenticated DELETE in a third, all visible side-by-side without any state bleeding between them.
Add Tab ( + )
Click the + button on the right of the tab bar to open a fresh, blank request context. Up to 6 tabs allowed.
Switch Tabs
Click any tab pill to instantly switch. Your previous URL, method, body, auth, and response are all preserved.
Method Badge
Each tab pill shows a colour-coded method badge (GET green, POST indigo, PUT amber, DELETE red) for at-a-glance identification.
Live Spinner
A spinning indicator appears on the tab pill while its request is in-flight, so you always know which tab is loading.
Reset Current Tab
The ↺ reset button clears only the active tab's state — URL, params, body, auth, and response — leaving all other tabs untouched.
6-Tab Hard Cap
To maintain performance, the + button is disabled once you reach 6 tabs. Close an existing tab to open a new one.
Why Use an Online HTTP / API Client?
API Clients are foundational utilities during backend and frontend integrations. Instead of writing curl commands or installing desktop software, this visual tool lets you structure endpoints, configure auth, and inspect responses inside a clean browser interface — instantly accessible from any device.
Our tool is a lightweight Postman alternative that loads in seconds with no registration, no installation, and no cloud sync. It is ideal for verifying public APIs, validating webhook destinations, checking JSON schema outputs, and running multiple endpoint tests in parallel using the multi-tab session feature.
HTTP Request Anatomy
Every API request contains key building blocks that dictate how servers process payloads:
Core Request Architecture
METHOD → GET, POST, PUT, DELETE
URL → https://api.domain.com/v1/users
PARAMS → ?page=1&limit=20 (auto-appended)
HEADERS → Authorization: Bearer <token>
Content-Type: application/json
BODY → { "username": "dev_coder" }
RESPONSE → STATUS (200 OK, 404 Not Found…)
HEADERS (Cache-Control, ETag…)
BODY (JSON, HTML, plain text)Supported Authentication Methods
Configure per-tab authentication without affecting other open sessions. Each auth type is isolated to the tab it was set in.
| Auth Type | How It Works | Sent As | Extra Feature |
|---|---|---|---|
| Basic Auth | Base64-encodes username:password automatically | Authorization: Basic … | 👁 Password visibility toggle |
| Bearer Token | Prefixes your raw token string | Authorization: Bearer … | — |
| JWT | Sends JSON Web Token as a Bearer | Authorization: Bearer … | — |
| API Key | Custom key name + value | Header or Query param | Configurable location |
| None | No auth header added | — | — |
Basic Auth — Password Visibility Toggle
The password field in the Basic Auth panel includes an eye (👁) icon button. Clicking it reveals the password in plain text so you can verify the exact credentials before sending. The toggle is per-tab — different tabs can independently show or hide their passwords. Credentials are encoded only in your browser and never stored externally.
Method Examples
HTTP request templates — inspect & copy
Select any method below to view standard configurations. Open each in a different tab to test them in parallel.
Request URL
GET https://jsonplaceholder.typicode.com/todos/1
Headers: Accept: application/json
Body Payload
None
💡 Retrieves a representation of a resource. Ideal for fetching user data, configuration, or item lists. Open a new tab and paste this URL to test simultaneously.
Common HTTP Methods Comparison
Understanding standard HTTP semantics is essential when designing REST integrations. Use a separate tab for each method to test your full CRUD API surface in one view.
| Method | Idempotent | Has Request Body | Purpose |
|---|---|---|---|
| GET | Yes | No | Fetch details of a resource without side effects. |
| POST | No | Yes | Create a new resource on the server. |
| PUT | Yes | Yes | Replace or update a complete resource model. |
| DELETE | Yes | No | Permanently remove a resource by ID. |
How to Test an API — Step-by-Step
1
Open a Request Tab
A fresh tab opens automatically. Click '+' to add up to 5 more tabs for parallel endpoint testing across GET, POST, PUT, and DELETE.
2
Enter URL & Method
Type your endpoint URL and choose the HTTP method. Paste a URL with a query string and the tool will auto-extract parameters into the Params tab.
3
Configure Auth
Go to the Auth tab. Choose Basic Auth (use the eye icon to verify your password), Bearer Token, JWT, or API Key with header/query placement.
4
Set Headers & Body
Add custom request headers in the Headers tab. Switch to Body to set a JSON or plain-text payload for POST and PUT requests.
5
Send & Inspect
Hit 'Send'. The response panel shows status code, time in ms, body size, formatted JSON or raw text output, and all response headers.
6
Reset or Switch Tab
Hit ↺ Reset to clear the current tab for a fresh call. Switch to another tab to compare responses without losing your work.
API Testing Scenarios
- JSON Response Validation — verify schemas match expected shapes
- Auth Token Verification — test header authentication across different tab configs
- Speed Benchmarking — compare roundtrip latency across multiple endpoints in parallel
- CORS Checking — detect cross-origin policy issues in browser sandboxes
- Parameter Debugging — test complex query strings and body parsers side by side
- Credential Auditing — use the Basic Auth password toggle to verify credentials before sending
Key Tool Features
- Multi-tab sessions — up to 6 fully isolated request contexts
- Per-tab reset button — clears only the active tab, other tabs untouched
- Chrome-style tab bar with method badges, live spinner, and close buttons
- GET, POST, PUT, and DELETE HTTP methods
- URL parameter auto-extraction into editable key-value rows
- Basic Auth with password visibility toggle (👁 icon)
- Bearer token, JWT, and API Key (header or query) authentication
- JSON and plain-text request body editors
- Timing metrics — response time in milliseconds, body size in bytes
- Full response parser — status code, formatted body, and all headers
- 100% client-side sandbox — credentials never leave your browser
- No install, no registration, no cloud sync required
Security and Privacy Guarantee
Unlike desktop tools that aggregate histories and sync credentials to centralized cloud services, this web client is completely local and private. Every fetch runs sandboxed in your browser's native Fetch API. No request data, headers, tokens, or body payloads ever touch our servers.
Multi-tab session data lives entirely in React component state for the lifetime of the page. Refreshing or closing the tab clears everything instantly. API keys set in one tab are isolated from all other tabs by design — no accidental credential bleed between sessions.
💡 Tip: Ensure your target API is served over HTTPS to protect transmission across local networks. Basic Auth credentials are Base64-encoded in-browser — always use HTTPS in production.
Frequently Asked Questions
Everything about multi-tab sessions, authentication, CORS, reset, and privacy.