Nouplo

Developer tools that stay on your machine

These utilities run on every keystroke, in your browser, with no server round trip. That makes them fast, and it means a JWT, a hash input or a config you paste here is never transmitted anywhere.
⛓ URL encoder / decoder Percent-encoding both ways, worked out as you type. ⌗ SQL formatter A query you can read, from one you were handed. ‹› XML formatter Indented to be read, or squeezed to one line to be sent. ◒ Colour converter HEX, RGB, HSL and CMYK — plus the contrast ratio that decides readability. ♭ Password generator Made on your device, by the browser's cryptographic generator. Nothing is sent anywhere. {} JSON Formatter Paste JSON, get it indented, minified or validated instantly. Your data stays on this page. • Regex Tester Type a pattern, paste some text, and see every match and capture group as you go. ♭ JWT Decoder Paste a JSON Web Token and read its header and claims. The token never leaves your browser. ◴ Cron Parser See 0 */6 * * 1-5 as the dates it will actually run, and what each field allows. ∿ Base64 Convert text to Base64 and back, with correct UTF-8 handling and an optional URL-safe alphabet. # Hash Generator Get the MD5, SHA-1 or SHA-2 digest of any text, computed on your device. • UUID Generator Create UUID v4 or v7 identifiers in bulk, generated on your device with a secure random source.
▤ Timestamp Converter Paste an epoch value or a date and see it in UTC, local time and ISO 8601. ‹› HTML formatter Indented so you can read it, or squeezed so you can ship it. ◒ CSS formatter One declaration to a line, or the whole file on one. • JavaScript minifier Smaller, and provably the same code. {} JSON to types A sample in, a type out. ⌗ CSV to SQL A pasted table, ready to run. ▦ Markdown table Paste a spreadsheet, get a table that lines up. ≠ JSON diff What actually changed, as a path. ✓ YAML validator Does it parse — and does it mean what you think? ⛶ Subnet calculator What that slash actually covers. 🔒 chmod calculator 755 one way, rwxr-xr-x the other. ♭ htpasswd generator The line Apache wants, hashed on your own machine. ☐ User-Agent parser Past the compatibility lies, to what it actually is. ⛓ Query string parser The parameters of a URL, one per line. ‹› HTML entities Escaped so it shows, or decoded so you can read it. ◐ Contrast checker Whether anyone can actually read it. ⛓ Slug generator Titles in, URLs out. ∿ Number base converter 0x2F is 47, and nobody remembers that. ∿ ASCII and Unicode table The code for a character, or the character for a code. ⛶ HTTP status codes What the number means, and when to send it. ∿ MIME types What to put in Content-Type, and what happens when it is wrong. ▤ Cron expression generator A schedule in words, an expression out. {} JSONPath evaluator The path, your document, and what it actually selects. ♭ bcrypt hash checker Does this password match this hash? ◒ CSS gradient generator Colours in, a declaration out. ◒ CSS box-shadow generator The declaration, not a canvas you drag. ∿ cubic-bezier easing The curve, as a table you can actually read. ⇄ XML to JSON With the rules stated, so nothing surprises you. ⛶ HTTP headers What the header does, and what people get wrong about it. ⛶ What is my IP The address websites see when you connect. 🔒 Password strength checker How long it would actually hold up.

How the developer tools work

Small utilities for the moments in a working day when you need an answer, not a library: format and validate JSON, test a regular expression against real text, read a JWT, turn a cron expression into plain words and upcoming run times, encode Base64 and URLs, make hashes, UUIDs and passwords, convert Unix timestamps and colours, and tidy SQL, XML, HTML and CSS.

They run in your browser on every keystroke, with no server round trip, so the result is there as you type and the tools keep working offline. It also means that a token, a password, a config file or a customer record you paste is never transmitted. The one tool that has to use the network says so on its page: What is my IP asks our server which address you are connecting from.

There is no account, no sign-up and no daily limit on these tools. Pro exists for the file tools on the other Nouplo sites; nothing on this one needs it.

Frequently asked questions

Is it safe to paste a real JWT or API response here?
The decoding and formatting run in your browser, and nothing you paste is sent to Nouplo or anyone else. A live token is still a credential, though, so treat it like a password and avoid shared computers. Note that JWT Decoder reads the header and claims but does not verify the signature; that needs the issuer’s key and belongs on your server.
Why is my JSON invalid?
The usual causes are a trailing comma, single quotes instead of double quotes, a comment, or a value cut off when it was copied. JSON Formatter points to the line and column where parsing stopped, and JSON diff shows what changed between two versions once both are valid.
How do I check what a cron expression does before I deploy it?
Paste it into Cron Parser: it says in words when the job runs and lists the next run times, so a 0 */6 * * 1-5 that you meant for weekends is caught before it fires. Cron expression generator builds one from a few choices if you would rather not write it by hand.
Are the passwords and hashes made here secure?
Password generator draws from your browser’s cryptographic random generator, not Math.random, and the passwords are never transmitted. Hash Generator computes MD5, SHA-1 and SHA-2 on your device. MD5 and SHA-1 are fine for checksums but not for storing passwords; use a slow, salted algorithm such as bcrypt or Argon2id on your server for that, and bcrypt hash checker to test a hash against a password.
How do I convert a Unix timestamp to a date?
Timestamp Converter takes an epoch value in seconds or milliseconds, or a date, and shows it in UTC, in your local time and as ISO 8601. A timestamp with 13 digits is in milliseconds, one with 10 is in seconds.