$devtoolkit.sh/for/backend-developers

Dev Tools for Backend Developers

Backend developers work with structured data, APIs, databases, authentication, and scheduled tasks across a wide range of languages and frameworks. Whether you are debugging a JWT token, formatting a complex SQL query, generating test data, parsing a cron expression, or validating JSON from an external API, having reliable browser-based tools at hand saves significant context-switching time. This collection is curated for the everyday backend development workflow.

{}JSON Formatter[HOT]

Pretty-print and format JSON with proper indentation.

{}JSON Validator[HOT]

Check if your JSON is valid and find syntax errors.

{}JSON Diff[HOT]

Compare two JSON objects and highlight added, removed, and changed keys.

->JSON to YAML[HOT]

Convert JSON to YAML format with proper indentation.

YMLYAML Formatter

Format and beautify YAML with consistent indentation (2 or 4 spaces).

YML✓YAML Validator

Validate YAML syntax and preview the parsed JSON representation.

SQLSQL Formatter

Format and beautify SQL queries with proper indentation and uppercase keywords.

SQL→SQL Result to CSV

Convert tab- or pipe-separated SQL CLI output into clean CSV format.

->CSV to JSON[HOT]

Convert CSV data to a JSON array of objects.

.*Regex Tester[HOT]

Test regular expressions against text with real-time match highlighting.

#Hash Generator[HOT]

Generate SHA-1, SHA-256, SHA-384, and SHA-512 cryptographic hashes from any text.

#HMAC Generator

Generate HMAC-SHA-256/384/512 message authentication codes using a secret key.

JWTJWT Decoder[HOT]

Decode and inspect JSON Web Token header and payload.

JWTJWT Generator

Build and sign JWTs with HS256 using the Web Crypto API.

*/5Cron Parser

Parse cron expressions and see next execution times in plain English.

@Unix Timestamp to Date[HOT]

Convert Unix timestamps to human-readable dates and vice versa.

#UUID Generator[HOT]

Generate random UUIDs (v4) for use as unique identifiers.

#Fake Data Generator

Generate rows of realistic fake data with configurable columns.

B64Base64 Encode[HOT]

Encode text or binary data to Base64 format.

B64Base64 Decode[HOT]

Decode Base64-encoded strings back to readable text.

#cURL Builder

Build cURL commands visually with URL, method, headers, body, and auth.

~HTTP Status Reference

Searchable reference of all HTTP status codes with descriptions.

FAQ

How do I quickly check what a JWT contains?
Use the JWT Decoder to paste any JWT and instantly see the header algorithm, payload claims (user ID, roles, expiry), and verify the structure. The tool shows the decoded payload alongside the raw base64url components.
What is the fastest way to generate realistic test data?
The Fake Data Generator creates realistic user profiles, addresses, emails, and custom data sets that you can export as JSON or CSV. The JSON Data Generator lets you define a custom schema with types and constraints for more specific test fixtures.
How do I convert a cron expression to human-readable form?
Paste any cron expression into the Cron Parser and it translates it to plain English, shows the next 10 scheduled run times, and validates the expression. The Crontab Generator helps you build new expressions from natural language descriptions.

Tools for Other Roles

/for/backend-developersv1.0.0