What is dot notation for JSON?

A compact way to address a value inside nested JSON: keys separated by dots, array elements by bracketed indexes. result.items[0].id means: take the result key, its items array, the first element, and that element's id.

Is my JSON uploaded anywhere?

No. Parsing and extraction run entirely in your browser with plain JavaScript. Nothing you paste leaves the page.

How do I access nested arrays?

Chain bracket indexes: data.rows[2][0] takes the third row, then its first element. Negative indexes aren't supported; use the explicit position.

JSON Path Tester

Paste a JSON response, type a path, see what comes out. Built for writing API assertions without the guess-deploy-check loop. Everything runs locally in your browser.

JSON

Path

Extracted value

Type

Full extraction

Path syntax

Keys separated by dots: result.healthy
Array elements by index: result.peers[0], chainable as rows[2][0]
Keys containing dots can be bracket-quoted: headers["content.type"]
An empty path returns the whole document

Where this matters for monitoring

A 200 status code means the server answered, not that it's healthy. Plenty of broken systems return 200 with "healthy": false or a stale block height in the body. Asserting on a value inside the response is the difference between monitoring the web server and monitoring the service. This is exactly how body assertions work in failover.io monitors: you give a path and a condition, and the check fails when the extracted value doesn't satisfy it, even if the HTTP status looks fine.

If you're monitoring a blockchain node, the path you want is usually the block height or slot number in the JSON-RPC response. There's a full walkthrough in our guide on monitoring JSON-RPC blockchain node uptime.

Related tools

Cron Expression Tester: for scheduled jobs hitting those APIs.
SLA Uptime Calculator: what "up" needs to mean, in numbers.

Assert on what the body says, even when the status lies

failover.io monitors check your endpoints up to every 15 seconds and can assert on any path in the JSON body. When an assertion fails, the alert chain escalates from email to SMS to a phone call until someone acknowledges. Free plan: 5 monitors, no card.

Start monitoring free