a2zutil.dev

Frequently asked questions

Everything people usually ask about a2zutil.dev.

General

Yes — every tool currently on the site is free to use, with no trial, no usage limits and no signup.

No. There is no signup and no login anywhere on the site — every tool works anonymously the moment the page loads.

No for the formatters — they process everything locally in your browser and never send your input anywhere. The Webhook and temporary email inbox are exceptions: deliveries sent to your temporary URL or address are stored briefly so you can inspect them, then expire. The BIN checker is the other exception — it sends only the first 6-8 digits of a card number to a third-party lookup API, never a full card number.

A JSON formatter and validator, a JSON to CSV converter, a JSON compare/diff tool, a SQL formatter, a case converter, a Base64 encoder/decoder, a URL encoder/decoder, a UUID v4 generator, a Text Transform tool, Find & Replace, a BIN/IIN checker, a temporary email inbox, and a live Webhook.

Yes. Every page is built mobile-first, which matters because a lot of quick checks happen on a phone.

Once a page has loaded, the formatter tools keep working without a network connection because all processing is local. The Webhook, temporary email inbox and BIN checker need a connection.

The formatters never transmit your input, so they are safe for internal payloads and queries. As always, avoid pasting live secrets or credentials anywhere, here included.

There is no user tracking of tool inputs. Tool areas are kept free of clutter so the utilities stay fast.

Up to 7 days or 100 captured requests, whichever comes first. After that it stops accepting new deliveries and moves to an archived state; the page shows the exact remaining time while a session is active.

Use the Request a tool button on any page, or email it in via the contact page. Tools are prioritised by how often people need them — a JWT decoder and Unix timestamp converter are already in progress.

Related tools

JSON Formatter

Format, minify and validate JSON, with auto-repair for common invalid JSON.

JSON ↔ CSV

Convert a JSON array of objects to CSV, or back.

JSON Compare

Diff two JSON documents, path by path.

SQL Formatter

Indent queries with keyword casing options.

Case Converter

camelCase, snake_case, kebab-case, PascalCase and more, all at once.

Base64 Encoder / Decoder

Encode or decode Base64, including the URL-safe alphabet.

URL Encoder / Decoder

Percent-encode or decode a URL component.

UUID v4 Generator

Generate one or many cryptographically random UUID v4s.

Text Transform

Lines to a delimited list, and back.

Find & Replace

Regex, whole-word and case-sensitive search and replace, in place.

BIN Checker

Card issuer lookup from a BIN/IIN.

Temporary Email

A disposable inbox for live-testing incoming mail.

Webhook

Inspect live webhook deliveries.