โ† DevTools/๐Ÿ“–Documentation
๐Ÿ” Verify๐Ÿงฐ Workbench

Tool reference

What each of the 16 tools checks, what it proves, and what it deliberately does not claim.

โฑ

CronBuilder

LIVE

Generate, validate, and understand cron expressions. CronBuilder gives you live feedback, plain-English explanations, upcoming run times, and ready-to-paste code for every platform.

โœ๏ธ
Live expression input

Type any cron expression and get instant validation. Each field (minute, hour, day, month, weekday) is colour-coded for fast visual parsing.

๐Ÿ’ฌ
Plain-English explanation

Converts your cron into a human-readable sentence โ€” 'Every 5 minutes, every hour, every day' โ€” using the cronstrue library.

๐Ÿ“…
Next scheduled runs

Shows the next 8 upcoming run times in your local timezone so you can verify the schedule is exactly what you intend.

โšก
12 quick presets

Every minute, every 5 minutes, daily 9am, weekdays 9am, monthly 1st, and more โ€” click to load instantly.

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Code snippets

Export to Node.js, Python, Linux crontab, GitHub Actions, and Docker in one click.

๐Ÿ”—
Shareable URL

The cron expression is encoded in the URL: /tools/cronbuilder?cron=*/5+*+*+*+*

Cron syntax reference

Minute

0โ€“59

Hour

0โ€“23

Day

1โ€“31

Month

1โ€“12

Weekday

0โ€“7

Cron examples
*/5 * * * *        โ†’ Every 5 minutes
    0 9 * * 1-5        โ†’ Weekdays at 9:00 AM
    0 0 1 * *          โ†’ First day of every month at midnight
    30 8,20 * * *      โ†’ Twice daily at 8:30 AM and 8:30 PM
    0 */6 * * *        โ†’ Every 6 hours

Special characters

These work in any field:

*Any value โ€” matches every possible value for that field
*/nEvery n โ€” e.g. */15 in minute = every 15 minutes
n-mRange โ€” e.g. 1-5 in weekday = Monday to Friday
a,bList โ€” e.g. 0,6 in weekday = Sunday and Saturday
n/mStep from n โ€” e.g. 2/5 = starting at 2, every 5
โšก

RegexLab

LIVE

Build, test, and understand regular expressions visually. RegexLab shows you what each part of your pattern does, highlights matches in your test text, and exports working code in 4 languages.

๐ŸŽจ
Live token breakdown

Every character in your pattern is tokenized and colour-coded โ€” literals (green), escapes (teal), quantifiers (orange), anchors (purple), groups (blue), meta (red). Click any token for a plain-English explanation.

โœ๏ธ
Live match highlighting

Paste any text below your pattern and matches are highlighted instantly. Multiple matches use different colours for easy scanning.

๐Ÿ“‹
Match list view

Switch to List view to see every match with its index position, length, and captured group values.

๐Ÿ“š
22-pattern library

Prebuilt patterns for email, URL, phone numbers (US + Bangladesh), IPv4, dates, hex colors, usernames, passwords, SQL injection, XSS, Markdown parsing, and more.

</>
Code export

Export your pattern as ready-to-use JavaScript, Python 3, PHP, or Go code with one click.

๐Ÿ”—
Shareable URL

Pattern, flags, and test text are all URL-encoded. Share exactly what you're testing.

Regex flags

g

Global

Find all matches, not just the first one

i

Ignore case

Makes the match case-insensitive โ€” a matches A

m

Multiline

^ and $ match start/end of each line, not just the string

s

Dotall

. matches any character including newlines

u

Unicode

Enables full Unicode support and Unicode escape sequences

y

Sticky

Match only from the position indicated by lastIndex

Token types

Literalabc

Exact character matches

Escape\d \w

Shorthand character classes

Class[a-z]

Character sets and ranges

Quantifier* + {3}

How many times to match

Anchor^ $ \b

Position assertions

Group(abc)

Capture and non-capture groups

Meta. |

Special metacharacters

Common pattern examples

RegexLab patterns
Email validation      ^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$
    BD phone number       ^(\+8801|01)[3-9]\d{8}$
    URL (HTTP/HTTPS)      https?://(www\.)?[\w-]+(\.[\w-]+)+([\w.,@?^=%&:/~+#-]*)
    IPv4 address          ^(\d{1,3}\.){3}\d{1,3}$
    Strong password       ^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[@$!%*?&]).{8,}$
    ISO date YYYY-MM-DD   ^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$
{}

JSONCraft

LIVE

JSONCraft is live with 6 features: Format with syntax highlighting, Validate with stats, TypeScript interface generator, Zod schema generator, CSV export, and Sort keys โ€” all processed locally in your browser.

โœ…
Format & beautifyLIVE

Paste minified or malformed JSON and get it beautifully indented with correct whitespace.

โœ…
ValidateLIVE

Instant syntax error detection with precise line/column error reporting.

๐Ÿ”„
MinifyLIVE

Remove all whitespace for production payloads or API requests.

๐Ÿ”ง
TypeScript interface generatorBETA

Auto-generate typed TypeScript interfaces from any JSON object.

๐Ÿ”ง
Zod schema generatorBETA

Generate Zod validation schemas directly from JSON structure.

๐Ÿ“‹
Diff modeSOON

Compare two JSON documents and highlight the differences.

๐Ÿ“‹
CSV / YAML exportSOON

Convert JSON arrays to CSV or transform to YAML format.

What JSONCraft can do

โœจ
Format & Beautify

Syntax-highlighted output with colour-coded keys, strings, numbers, booleans, and nulls

โœ…
Validate

Instant error reporting with stats: key count, nesting depth, arrays, strings, numbers

๐Ÿ”ท
TypeScript Interface

Auto-generate typed interfaces from any JSON structure with nested types

๐Ÿ›ก
Zod Schema

Generate z.object() schemas with inferred type export ready for your project

๐Ÿ“Š
CSV Export

Convert JSON arrays to CSV with proper escaping and one-click download

๐Ÿ”ค
Sort Keys

Recursively sort all object keys Aโ†’Z for clean diffs and version control

๐Ÿงช

APITester

LIVE

Build and send HTTP requests directly from your browser. See responses with syntax-highlighted JSON, timing, size, and response headers. No install required.

๐ŸŒ
7 HTTP methods

GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS โ€” each colour-coded so you always know which method is active.

๐Ÿ”‘
3 auth types

Bearer token, Basic auth (username + password), and API Key (custom header name). Auth is injected into the request headers automatically.

๐Ÿ“ฆ
Request body

JSON editor with monospace green text, HTML form (key-value pairs), and raw text. Content-Type header is set automatically.

๐ŸŽจ
Syntax-highlighted response

JSON responses are colour-coded: keys in blue, strings in green, numbers in teal, booleans in amber, nulls in red.

โฑ
Timing + size

Response time in ms and body size shown in the header bar. Green under 200ms, amber under 1s, red above.

๐Ÿ’พ
Save requests (Pro)PRO

Save up to 100 API requests โ€” URL, method, headers, auth, and body โ€” and reload them instantly.

โš  CORS note

Requests are sent directly from your browser, so APIs that don't set CORS headers will be blocked. This affects public APIs that only allow server-to-server calls. For those, use APITester to build and copy the request, then run it from your terminal with curl.

๐Ÿ“

DiffViewer

LIVE

Compare any two pieces of text with line-level diff highlighting. Uses the Myers diff algorithm โ€” the same algorithm used by Git.

โฌ›
Split view

Original and modified side-by-side with line numbers. Deletions on the left in red, insertions on the right in green.

๐Ÿ“„
Unified view

Classic unified diff format with + and โˆ’ prefixes. Mirrors what you see in git diff or GitHub PR reviews.

๐Ÿ“Š
Diff stats

Live counts of lines added, removed, and unchanged shown in the header as you type.

๐Ÿ“‹
Copy as patch

Export the diff in standard unified patch format โ€” paste directly into a .patch file or GitHub comment.

๐Ÿงช
Sample pairs

JSON config, code function refactor, and SQL query โ€” load instantly to see the diff engine in action.

Works great for

โœ“JSON config changes
โœ“Code review before committing
โœ“SQL query optimisation
โœ“API response comparison
โœ“Markdown document edits
โœ“Environment variable files
๐Ÿ”—

URLInspector

LIVE

Paste any URL and instantly see every component colour-coded and labelled. Build URLs visually and copy query parameters one by one.

๐ŸŽจ
Colour-coded breakdown

Protocol (amber), hostname (green), port (blue), path (teal), query string (purple), fragment (grey) โ€” visually distinct at a glance.

๐Ÿ“‹
Query parameter table

Each key=value pair shown separately with individual copy buttons. Useful for debugging API calls with many parameters.

๐Ÿ”ง
URL Builder

Compose a URL visually: pick protocol, enter host, path, fragment, and add/remove query params dynamically. Output updates live.

โšก
Auto-prepend https://

Paste a bare hostname like google.com and URLInspector automatically prepends https:// so parsing always works.

๐Ÿ”‘

JWT Decoder

LIVE

Paste any JWT to instantly decode its header and payload, check expiry status, and verify HMAC signatures โ€” all in your browser.

๐Ÿ”
Instant decode

Header and payload are decoded and pretty-printed the moment you paste a token โ€” no button needed.

โฑ
Expiry & timing claims

exp, iat, and nbf claims are parsed into human-readable dates with a live relative-time countdown and a clear valid/expired badge.

โš 
Insecure token warnings

Flags tokens using alg: none โ€” a known JWT vulnerability where the signature is stripped entirely.

โœ…
HMAC signature verification

Enter the signing secret to verify HS256/HS384/HS512 signatures locally via the Web Crypto API. RS/ES/PS algorithms need a public key and aren't supported.

๐Ÿ”’ Security note

JWTs are encoded, not encrypted โ€” anyone can read the header and payload without a secret. Never store passwords or sensitive secrets in a JWT payload. Saving is intentionally not offered for this tool.

๐Ÿ”

HashLab

LIVE

Hash, encode, decode, and generate โ€” all processed locally using the browser's native Web Crypto API. Nothing leaves your device.

๐Ÿ”‘
SHA Hashing

SHA-1, SHA-256, SHA-384, SHA-512. All four generated simultaneously from your input. Copy any individually.

๐Ÿ“ฆ
Base64 Encode / Decode

Standard Base64 and URL-safe Base64 (replaces + โ†’ - and / โ†’ _ for use in URLs and JWTs).

๐Ÿ”—
URL Encode / Decode

encodeURIComponent / decodeURIComponent โ€” essential for building query strings and parsing URLs.

๐ŸŸฆ
Hex Encode / Decode

Convert text to its hexadecimal byte representation and back.

๐ŸŽฒ
UUID v4 Generator

Cryptographically random UUIDs using crypto.getRandomValues(). Generate 1, 5, 10, or 20 at once.

โšก
NanoID Generator

21-character URL-safe unique IDs โ€” shorter than UUID, same entropy. Popular in modern apps.

๐Ÿ’ก Why no MD5?

MD5 is cryptographically broken and the Web Crypto API deliberately does not implement it. For checksums use SHA-256. For passwords use bcrypt (server-side only โ€” never hash passwords in the browser).

๐Ÿ“Š

CSVStudio

LIVE

Upload or paste CSV data and instantly get a sortable, filterable table. Inspect column statistics, then export to JSON, SQL INSERT, or Markdown โ€” all processed locally.

๐Ÿ“‹
Table view

Sortable columns (click any header), filterable rows, colour-coded numeric values in teal. Click any cell to copy its value.

๐Ÿ“ˆ
Column stats

Per-column analysis: row count, empty count, unique values, and for numeric columns: min, max, average, and sum.

๐Ÿ”
Auto-detect delimiter

Upload a file and CSVStudio automatically detects whether it uses commas, tabs, semicolons, or pipes.

</>
3 export formats

JSON Array (typed โ€” numbers stay numbers, nulls are null), SQL INSERT with your table name, and Markdown table.

โ†‘
File upload

Upload .csv, .tsv, or .txt files directly. The filename becomes the default SQL table name.

๐Ÿ’พ
Save datasets (Pro)PRO

Save CSV datasets for quick reload โ€” useful for reference data you use across multiple projects.

๐Ÿ“„

YAML โ‡„ JSON

LIVE

Convert between YAML and JSON in either direction โ€” essential for Docker Compose, Kubernetes manifests, and CI/CD config files.

โ‡„
Bidirectional

One swap button flips direction and carries your current output into the new input side.

๐ŸŒฒ
Nested structures

Handles nested mappings and sequences, including sequences of mappings (e.g. a list of service definitions).

โœจ
Inline flow syntax

Supports inline arrays [a, b, c] and inline objects {'{a: 1, b: 2}'} alongside standard block-style YAML.

๐Ÿ’พ
Save snippets (Pro)PRO

Save frequently converted config snippets and reload them across devices.

โš  Parser scope

This is a lightweight YAML subset parser built for common config files. It does not support multi-document YAML (---), anchors/aliases (& and *), or block scalars (| and >). For those, use a full YAML library in your build pipeline.

๐Ÿ—„

SQL Formatter

LIVE

Beautify raw SQL queries with proper keyword casing and clause-level indentation, or minify to a single line.

โœจ
Format mode

Breaks queries onto new lines at major clauses (SELECT, FROM, WHERE, JOIN, GROUP BY, ORDER BY, etc.) with consistent indentation.

๐Ÿ“ฆ
Minify mode

Collapses a formatted query back to a single line โ€” useful for logging or embedding in application code.

๐Ÿ” 
Keyword casing

All recognized SQL keywords are automatically uppercased for consistency, regardless of how you typed them.

๐Ÿ’พ
Save queries (Pro)PRO

Save frequently used queries and reload them across devices.

โš  Formatter scope

This is a heuristic formatter, not a full SQL parser. It covers common ANSI/MySQL/PostgreSQL SELECT, INSERT, UPDATE, DELETE, and CREATE TABLE statements well, but deeply nested subqueries or unusual vendor-specific syntax may not format perfectly.

๐Ÿ”ง

.env Comparer

LIVE

Compare two .env files to spot missing variables and value drift between environments โ€” for example, local vs. production.

๐Ÿ”
Key-level diff

Every key is categorized as Same, Different, Only in A, or Only in B โ€” click any stat card to filter the list.

๐Ÿ™ˆ
Values masked by default

Values are partially masked (e.g. abโ€ขโ€ขโ€ขโ€ขโ€ขโ€ขโ€ขโ€ขyz) until you explicitly click Reveal โ€” protects secrets from shoulder-surfing.

๐Ÿ“„
Generate .env.example

One click produces a template with every key from both files and empty values โ€” safe to commit to version control.

๐Ÿ•

Timestamp Converter

LIVE

Convert Unix timestamps to human-readable dates and back, with live current time and timezone support.

๐Ÿ”ด
Live current time

Unix seconds and milliseconds update every second, so you always have a reference point.

๐Ÿ”ข
Auto-detects seconds vs milliseconds

Paste a 10-digit or 13-digit timestamp and it's interpreted correctly without needing to specify the unit.

๐ŸŒ
Timezone selector

19 common timezones covering major regions โ€” auto-detects your browser's timezone on load.

๐Ÿ“‹
7 output formats

Unix seconds/ms, ISO 8601, RFC 2822, localized timezone string, relative time, and day of week โ€” each with a one-click copy.

๐ŸŽจ

ColorSystemPro

LIVE

Input one hex color and get a complete design system โ€” 11-step scale, neutral palette, WCAG contrast ratios, dark/light mode preview, and export in 5 formats. Pure browser math, no AI.

๐ŸŽจ
11-step color scale

Steps 50โ€“950 generated from your brand color using HSL interpolation, matching Tailwind's methodology. Click any swatch to copy its hex.

โฌ›
Hue-tinted neutral scale

Not plain grey โ€” a subtly hue-shifted neutral scale that feels designed and cohesive with your brand color.

โœ…
WCAG contrast table

Every scale step tested against white and black with AA and AAA pass/fail badges. Know exactly which steps are safe for text.

๐ŸŒ™
Dark & light mode preview

Live UI mockup using your generated scale. See how your colors look in both modes before committing.

๐Ÿ’พ
Save palettes (Pro)PRO

Save up to 100 named palettes and reload them instantly across devices.

</>
5 export formats

CSS Variables, Tailwind Config, SCSS variables, JSON Design Tokens, and Dark Mode CSS โ€” ready to paste into your project.

Export formats

CSS Variables--color-primary-500: #4F8EF7;
Tailwind Configcolors: { primary: { 500: '#4F8EF7' } }
SCSS$primary-500: #4F8EF7;
JSON Tokens{ "primary": { "500": "#4F8EF7" } }
Dark Mode CSS--bg: #07090F; --surface: #111827;
๐Ÿ”’

Password Generator

LIVE

Generate cryptographically secure passwords or memorable passphrases, with entropy calculation and bulk generation.

๐ŸŽฒ
Cryptographically secure

Uses crypto.getRandomValues() โ€” the same secure random source browsers use for encryption keys, not Math.random().

๐Ÿ”ก
Configurable character sets

Toggle uppercase, lowercase, digits, and symbols independently. Optionally exclude visually ambiguous characters (0/O, 1/l/I).

๐Ÿ“–
Passphrase mode

Generate word-based passphrases (e.g. crown-falcon-marble-42) from a built-in word list โ€” easier to type and remember, still high entropy.

๐Ÿ“Š
Entropy & strength rating

Every generated password shows its entropy in bits and a Weak/Fair/Good/Strong rating based on that value.

๐Ÿ“ฆ
Bulk generation

Generate 5, 10, or 20 at once with copy-all support.

๐Ÿ’ก Why no saving?

Generated passwords are intentionally not saveable here. Use a dedicated password manager to store credentials โ€” a browser utility tool is not the right place for that.

๐Ÿงพ

InvoiceZen

LIVE

Create professional PDF invoices in under 60 seconds. No account, no uploads, no server โ€” everything is processed locally in your browser. Works for freelancers, agencies, and small businesses.

โœ๏ธ
Edit & Preview modes

Fill in your details in Edit mode, then switch to Preview to see the finished invoice exactly as it will print.

โ†“
PDF download

Uses the browser's native print dialog targeting only the invoice element. No jsPDF or server needed โ€” clean A4 output.

๐Ÿ’ฐ
8 currencies

USD, BDT, EUR, GBP, CAD, AUD, SGD, INR โ€” with correct currency symbols automatically applied throughout.

๐Ÿงฎ
Automatic totals

Subtotal, discount (%), tax (%), and total calculated live as you type. Add or remove line items dynamically.

๐ŸŽจ
Custom accent color

Your chosen color is applied to the invoice header, table headers, and total bar โ€” instant brand identity.

๐Ÿ’พ
Save invoices (Pro)PRO

Save up to 100 invoice templates. Reload a previous client's invoice, update the date and items, and export in seconds.

{}
Copy as JSON

Export the full invoice data as JSON for your own records or to import into accounting software.

๐Ÿ”’ Privacy note

InvoiceZen processes everything locally. Your client names, amounts, and business details are never sent to any server. The PDF is generated using your browser's print engine. Nothing is stored unless you explicitly save it with a Pro account.

๐Ÿ”ฎ

Coming Soon

The following tools are in design or development. Pro and Lifetime users get early access the moment each tool ships.

๐Ÿ“‹TermsDecoded
Planned

Paste any Terms of Service URL and get a plain-English summary of data sharing, auto-renewal traps, cancellation policies, and deletion rights.

DevTools by Hakeemify โ€” 16 tools live

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