Developer Debug Tools

Backend Developer Tools

Fast browser-based utilities for backend engineers debugging APIs, payloads, auth tokens, network traces, generated identifiers, timestamps, stacktraces, and service contracts. Paste the value you are investigating, inspect the result, and move to the next clue without opening a heavy workspace.

Backend debugging utilities

JSON Formatter JWT Decoder HAR File Analyzer OpenAPI Diff Checker Base64 Decoder Regex Tester Timestamp Converter UUID Generator ULID Generator Java Stacktrace Analyzer Curl Converter

Featured backend tools

Formatters

JSON Formatter

Pretty-print raw JSON, minify payloads, and inspect syntax errors with clear feedback.

API & Auth

JWT Decoder

Decode JWT headers and payloads, inspect claims, and check expiry fields at a glance.

Dev Debug Helpers

HAR File Analyzer

Analyze browser HAR files for slow requests, failed calls, duplicates, domains, and timing waterfalls.

API & Auth

OpenAPI / Swagger Diff Checker

Compare OpenAPI or Swagger JSON/YAML files for added, removed, and potentially breaking API changes.

Encoders & Decoders

Base64 Encode / Decode

Encode plain text to Base64 or decode Base64 back to readable text with Unicode support.

Validators & Testers

Regex Tester

Test regex patterns against sample text, inspect matches, and catch syntax errors immediately.

Converters

Timestamp Converter

Convert Unix seconds, Unix milliseconds, and ISO date strings with readable UTC and local output.

Validators & Testers

UUID Generator

Generate UUID values instantly in the browser for tests, requests, and correlation workflows.

Validators & Testers

ULID Generator

Generate sortable ULID values in the browser for modern identifier workflows.

Dev Debug Helpers

Java Stacktrace Analyzer

Find root causes in Java and Spring stacktraces, highlight application frames, and collapse framework noise.

Converters

cURL to Java

Turn common cURL commands into readable Java HttpClient examples with headers and body preserved.

FAQ

What are backend developer tools?

Backend developer tools help inspect API payloads, tokens, logs, network exports, timestamps, identifiers, and contract files while debugging services and integrations.

Do these tools require installation?

No. These utilities run in the browser, so backend engineers can format JSON, decode JWTs, review HAR files, compare OpenAPI specs, and convert values without installing a local package.

Which tools should I start with for API debugging?

Start with JSON Formatter for payload shape, JWT Decoder for auth claims, HAR File Analyzer for network behavior, OpenAPI Diff Checker for contract changes, and Timestamp Converter for time-based issues.

Can I use these tools with sensitive production data?

Redact secrets, bearer tokens, personal data, account IDs, and internal hostnames before pasting production debugging material into any tool or sharing generated output.

Related tools

Dev Debug Helpers

API Log Analyzer

Analyze API logs for ERROR/WARN/INFO counts, duplicate exceptions, correlation IDs, and timeline buckets.

API & Auth

HTTP Request Builder

Build HTTP requests safely and generate cURL and fetch snippets without turning the site into an open proxy.

API & Auth

Header Parser

Parse raw HTTP headers into readable key and value pairs for request and response debugging.

API & Auth

Query Param Parser

Parse URLs and raw query strings into decoded key and value pairs and rebuild them cleanly.

API & Auth

JWT Security Inspector

Decode JWTs, inspect expiry, issuer, audience, algorithm choices, and common token security mistakes.

Validators & Testers

JSON Schema Validator & Generator

Generate JSON Schema from sample JSON and validate payloads against required fields and basic types.