Is the Api Tester free to use?

Yes. Api Tester on Markvibe is 100% free with no sign-up, no credit card, and no usage limits.

Does the Api Tester upload my data to a server?

No. The Api Tester runs entirely in your browser using client-side JavaScript, so your input never leaves your device. The only exceptions are tools that explicitly need a third-party API (e.g. WHOIS, DNS, AI), which is clearly indicated.

Is the Api Tester safe and private?

Yes. Because processing happens locally in your browser, files, text, and other inputs are not stored on our servers. We don't require accounts and we don't track tool inputs.

Can I use Api Tester on mobile?

Absolutely. Every tool on Markvibe, including Api Tester, is fully responsive and works smoothly on iOS, Android, tablets, and desktops.

Do I need to install anything to use Api Tester?

No installation required. Api Tester is a pure web app — open the page and start using it instantly in Chrome, Firefox, Safari, Edge, or any modern browser.

What other developer tools do you offer?

Markvibe ships 184+ free tools including a full suite of developer tools. Scroll to "Related tools" below to discover more utilities in this category.

Api Tester — Free Online Tool

What is the Api Tester?

The Api Tester is a free online developer tools from Markvibe. Send GET/POST request and show response. It runs entirely in your browser — your data never gets uploaded — and works on desktop, tablet and mobile with no sign-up.

Reviewed by The Markvibe Team · Last updated 2026-06-28

Example

A worked example so you know exactly what to expect.

Input

(your input goes here)

Output

(the Api Tester runs in your browser and shows the result instantly)

How to use Api Tester

1Open the Api Tester on this page — it loads instantly with no sign-up.
2Paste or enter your input into the field above. You can paste, type, drag-and-drop, or upload depending on the tool.
3Set any options (format, size, mode) to match exactly what you need.
4Click the run button to run Api Tester in your browser.
5Review the result, then copy it to your clipboard or download the output file.