Mobile-Friendly Tester
Check if a URL is mobile-responsive — viewport, tap targets, font sizes.
- Web & Network
- Free to use
- Server processed
Your input
Run Mobile-Friendly Tester
Processed on our servers. Uploaded over TLS and deleted an hour later — 24 hours if you are signed in.
Three steps
How to use Mobile-Friendly Tester
- Step 01
Pick your input
Paste your text into the box above.
- Step 02
Configure & run
Click Run — there is nothing to configure. We process the file on our own infrastructure — no third-party APIs in the path.
- Step 03
Download the result
A JSON document is downloadable below.
Server-processed files are encrypted at rest with a per-tenant key and deleted an hour after upload — 24 hours if you are signed in. We do not use third-party processing APIs.
About mobile-friendly tester
Check if a URL is mobile-responsive — viewport, tap targets, font sizes. It sits in the web & network shelf alongside 64 other web & network tools, needs no account, and keeps the same behaviour whether you open it here or call it through the REST API.
It works from what you type in rather than a file and gives back JSON. The work happens on our servers, and the upload is encrypted per file and deleted an hour later — 24 hours if you are signed in. The same operation is available programmatically at POST /v1/web/mobile-friendly-tester.
Mobile-Friendly Tester questions
Where does Mobile-Friendly Tester process my file?
On our own servers. This tool needs more than a browser tab can provide, so the file is uploaded over TLS, processed on our infrastructure — no third-party processing APIs are in the path — and both the input and the result are deleted within an hour.
Do I need an account to use Mobile-Friendly Tester?
No. Mobile-Friendly Tester works without signing in, and that is not a trial — it is how the free tier works. An account only matters for things that need one to exist at all: larger server jobs against your quota, API keys, saved workflows and billing.
Can I run Mobile-Friendly Tester from my own code?
Yes. Every tool on the site is reachable from the REST API with the same slug — `mobile-friendly-tester` — and the same options as this page, so anything you can do here you can automate against your own files.
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