ALL TOOLS

Developer tools catalog

72 tools, 9 release checklists, 3 workflow pages, and 12 skill challenges across 9 canonical categories. Tool inputs stay in your browser. DDT uses Google Analytics and analytics cookies for page and allowlisted product-usage measurement; tool input and output are excluded. The CDN separately provides aggregate traffic counts. How privacy works.

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96 resources

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Compare & Diff 6
List Comparator
Diff two lists, find unique / common items, duplicates.
Compare & Diff
Text Diff
Side-by-side diff with word-level change detection.
Compare & Diff
JSON Diff
Compare two JSON payloads, ignoring key order.
Compare & Diff
Database Schema Diff + Migration Helper
Diff two CREATE TABLE schemas and generate ALTER migration hints.
Compare & Diff
CSV Join / Merge
Join, merge, and compare CSV files by key.
Compare & Diff
Compare Environments
Two- or three-way env diff: .env, ConfigMap, YAML, JSON, headers.
Compare & Diff
Data Formatters & Converters 16
JSON ↔ CSV
Bidirectional conversion with auto-format detection.
Data Formatters & Converters
JSON ↔ YAML
Convert API responses and configs locally between JSON and YAML.
Data Formatters & Converters
JSON Formatter
Validate, pretty-print, minify with tree view and secret detection.
Data Formatters & Converters
YAML Validator
Syntax errors with line/col, multi-doc, and schema checks for Kubernetes, Compose and CI configs.
Data Formatters & Converters
JSON Patch & Pointer
Apply RFC 6902 patches; resolve JSON Pointers.
Data Formatters & Converters
JSON Schema Validator
Validate JSON documents against a Draft-7 / Draft-2020 schema.
Data Formatters & Converters
JSONPath Tester
Extract values using JSONPath expressions.
Data Formatters & Converters
Synthetic Data Generator from JSON Schema
Generate schema-valid, realistic fake data from a JSON Schema (seeded).
Data Formatters & Converters
Schema Inspector
Infer and inspect the shape of any JSON document.
Data Formatters & Converters
CSV Viewer
Preview, auto-detect delimiter, trim, export.
Data Formatters & Converters
JSONL Log Viewer
Inspect newline-delimited JSON logs with field filters.
Data Formatters & Converters
SQL Formatter
Format SQL with indentation and keyword casing.
Data Formatters & Converters
CSV → SQL
Generate INSERT / UPSERT statements from CSV.
Data Formatters & Converters
SQL IN Builder
Build and chunk large SQL IN(...) clauses safely, with dialect-aware quoting.
Data Formatters & Converters
SQL Join Builder
Compose multi-table joins with previews.
Data Formatters & Converters
JSON to TypeScript
Generate TypeScript interfaces from a JSON sample, merging array shapes and optional fields.
Data Formatters & Converters
API & Web 15
cURL Converter
Convert curl to Fetch, Axios, Python, Java, Node — or fetch / axios / requests back to curl.
API & Web
API Debugging Studio
Multi-panel board: parse a cURL or HAR into headers, body, JWT and issues, or compare two entries.
API & Web
HAR Sanitizer
Redact secrets with custom rules, and export Postman / cURL / fetch packs.
API & Web
HTTP Headers
Parse / edit headers in a grid, detect duplicates.
API & Web
URL Parser
Parse URL parts, edit query params in a grid, rebuild.
API & Web
Request Snippet Builder
Build HTTP request snippets for any language.
API & Web
OpenAPI Client Snippets
Generate fetch / cURL / Axios calls from OpenAPI.
API & Web
OpenAPI Breaking Change Analyzer
Diff two OpenAPI/Swagger specs; classify breaking, risky, safe, doc.
API & Web
API Contract Test Generator
OpenAPI → curl / Jest / Playwright / Postman tests, with 4xx cases and shape assertions.
API & Web
CORS Debugger / Preflight Simulator
Simulate the browser CORS preflight & request checks; get fixes.
API & Web
OpenAPI → Postman
Export full Postman Collection v2.1 from OpenAPI.
API & Web
Postman Collection Inspector / Cleaner
Find secrets and dupes, diff two exports, and convert a collection to OpenAPI.
API & Web
XML / XPath / SOAP
Format XML, run XPath, inspect SOAP envelopes.
API & Web
XML ↔ JSON
Lossless conversion with attribute handling.
API & Web
GraphQL Playground
Validate GraphQL against your SDL schema, and generate cURL and fetch snippets.
API & Web
Security & Auth 9
Security Headers
Audit CSP directive by directive, HSTS, and cross-origin isolation headers.
Security & Auth
PII Detector
Find and redact personally identifiable information.
Security & Auth
Secrets Scanner
Detect API keys, tokens, and credentials in payloads.
Security & Auth
Phishing Link & Email Inspector
Check suspicious links, domains, senders, and raw email headers locally.
Security & Auth
JWT Decoder
Decode JWTs locally and verify HMAC signatures with a supplied secret.
Security & Auth
JWT & OAuth Toolkit
Sign / verify JWTs (HS/RS/ES), generate PKCE values.
Security & Auth
Certificate & PEM
Decode X.509 certs, inspect CSRs, split PEM bundles.
Security & Auth
JWK / JWKS / PEM
Convert between JWK, JWKS, and PEM key formats.
Security & Auth
Webhook Verifier
Verify Stripe / GitHub / Slack HMAC signatures.
Security & Auth
Encode / Decode 4
Base64 Encode / Decode
Encode or decode Base64 / Base64URL and data: URIs, or turn a local file into one.
Encode / Decode
URL Encoder
Encode / decode URL strings and query parameters.
Encode / Decode
Encoding Suite
Base64URL, Hex, Gzip / Deflate, Querystring conversions.
Encode / Decode
String Escape / Unescape
Escape & unescape strings for JSON, JS, SQL, regex, and HTML entities in both directions.
Encode / Decode
DevOps & Config 9
.env Converter
Convert between .env, .properties, JSON, bash export.
DevOps & Config
Kubernetes Helper
Generate / validate Deployment, Service, Ingress YAML.
DevOps & Config
Dockerfile Linter
Check unpinned images, root containers and cache-busting COPYs, with .dockerignore awareness.
DevOps & Config
Kubernetes / Helm Policy Inspector
Lint Kubernetes / Helm YAML against Pod Security Standards (baseline or restricted).
DevOps & Config
Docker Compose Helper
Generate / validate compose.yaml with healthchecks.
DevOps & Config
Cron Builder
Build cron expressions with guided UI and previews.
DevOps & Config
Cron Analyzer
Explain any cron expression and show next runs.
DevOps & Config
CIDR Subnet Calculator
IPv4 range, broadcast, usable hosts, masks and equal subnet splits for any CIDR block.
DevOps & Config
chmod Calculator
Convert Unix file modes between octal and symbolic, with special bits explained.
DevOps & Config
Utilities 13
Regex Tester
Pattern builder with presets and live match highlighting.
Utilities
Hash Generator
MD5, SHA-1, SHA-256, SHA-512 of text or a local file, plus HMAC and checksum verify.
Utilities
Password Generator
Passwords, tokens, test numbers with custom charsets.
Utilities
UUID Generator
v3, v4, v5 and v7 UUIDs with bulk generation and export.
Utilities
ULID, NanoID & KSUID Generator
Generate & decode ULID, NanoID, KSUID, CUID2, and Snowflake IDs.
Utilities
Unicode & Invisible Character Inspector
Detect and clean invisible, zero-width, bidi, and look-alike characters.
Utilities
Timestamp Converter
Unix epoch ↔ local / UTC / ISO with shareable links.
Utilities
Timezone & Date Math
Convert times across timezones, add/subtract durations.
Utilities
Line Tools
Trim, dedupe, sort, filter, wrap, prefix / suffix, join — filter before or after transforms.
Utilities
Lorem Ipsum
Generate placeholder paragraphs, sentences, words.
Utilities
Case Converter
Convert identifiers between camelCase, snake_case, kebab-case, CONSTANT_CASE and URL slugs.
Utilities
Color Converter
Convert HEX, RGB, HSL and OKLCH, and score any pair for WCAG contrast.
Utilities
Number Base Converter
Convert between binary, octal, decimal, hex and base 36 with exact BigInt maths.
Utilities
Checklists 9
API Release Checklist
Pre-release checklist: validate the OpenAPI spec, scan sample responses, and confirm versioning.
Checklist
CSV Reconciliation Checklist
Reconcile source vs. target CSVs during a migration — row counts, keys, and diffs.
Checklist
Dockerfile Review Checklist
Dockerfile review: lint locally, scan for secrets, and confirm image best practices.
Checklist
Env Variable Comparison Checklist
Compare environment variables across dev, staging, and production.
Checklist
HAR Sanitization Checklist
Strip cookies, auth headers, tokens, and PII from a HAR before sharing with support.
Checklist
JWT / OAuth Review Checklist
JWT / OAuth security review: decode locally and confirm alg, exp, audience, and scopes.
Checklist
Kubernetes Manifest Review
Parse YAML, scan for secrets, and confirm probes, limits, and security context.
Checklist
OpenAPI Compatibility Checklist
Walk every breaking-change category before bumping your OpenAPI version.
Checklist
Secrets & PII Pre-check
Pre-release scan for secrets and PII in diffs, logs, and sample payloads.
Checklist
Workflow pages 3
Workflow Gallery
Run browser-only developer workflows to clean, convert, validate, and transform JSON, CSV, JWTs, logs, configs, and URLs. Nothing leaves your browser.
Workflow page
Workflow Builder
Build, run, and save linear developer workflows in your browser. Chain tools like JSON formatter, Base64, and JWT decoder — nothing is sent to a server.
Workflow page
Workflow Import
Import a workflow JSON or open a share link. Workflows decode locally in your browser — nothing is uploaded.
Workflow page
Challenges 12
Regex Rescue
Build or choose the right regex to match valid strings and reject invalid ones.
Challenge
API Detective
Find the bug in an API request/response: status codes, headers, JWT, CORS, and more.
Challenge
Payload Patch
Pick the right transformation to fix a broken JSON payload.
Challenge
JSONPath Quest
Pick the JSONPath expression that returns the target output.
Challenge
Diff Detective
Spot the meaningful change between two snippets that may break consumers.
Challenge
JWT Heist
Identify what's wrong with a JWT — alg=none, expired, aud mismatch, RS↔HS confusion, and more.
Challenge
Cron TimeLock
Pick the cron that matches the intent, or spot the bug in the given cron.
Challenge
CSV Sleuth
Find the missing or duplicated row between two CSV snapshots.
Challenge
Dockerfile Watch
Pick the dangerous or non-reproducible line in a Dockerfile snippet.
Challenge
SQL Join Maze
Pick the SQL join that produces the target result set.
Challenge
Secret Hunter
Spot the leaked secret in a config or code snippet.
Challenge
Signature Forensics
Pick the reason this webhook signature verification failed.
Challenge

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Compare & Diff 6

List Comparator

Text Diff

JSON Diff

Database Schema Diff + Migration Helper

CSV Join / Merge

Compare Environments

Data Formatters & Converters 16

JSON ↔ CSV

JSON ↔ YAML

JSON Formatter

YAML Validator

JSON Patch & Pointer

JSON Schema Validator

JSONPath Tester

Synthetic Data Generator from JSON Schema

Schema Inspector

CSV Viewer

JSONL Log Viewer

SQL Formatter

CSV → SQL

SQL IN Builder

SQL Join Builder

JSON to TypeScript

API & Web 15

cURL Converter

API Debugging Studio

HAR Sanitizer

HTTP Headers

URL Parser

Request Snippet Builder

OpenAPI Client Snippets

OpenAPI Breaking Change Analyzer

API Contract Test Generator

CORS Debugger / Preflight Simulator

OpenAPI → Postman

Postman Collection Inspector / Cleaner

XML / XPath / SOAP

XML ↔ JSON

GraphQL Playground

Security & Auth 9

Security Headers

PII Detector

Secrets Scanner

Phishing Link & Email Inspector

JWT Decoder

JWT & OAuth Toolkit

Certificate & PEM

JWK / JWKS / PEM

Webhook Verifier

Encode / Decode 4

Base64 Encode / Decode

URL Encoder

Encoding Suite

String Escape / Unescape

DevOps & Config 9

.env Converter

Kubernetes Helper

Dockerfile Linter

Kubernetes / Helm Policy Inspector

Docker Compose Helper

Cron Builder

Cron Analyzer

CIDR Subnet Calculator

chmod Calculator

Utilities 13

Regex Tester

Hash Generator

Password Generator

UUID Generator

ULID, NanoID & KSUID Generator

Unicode & Invisible Character Inspector

Timestamp Converter

Timezone & Date Math

Line Tools

Lorem Ipsum

Case Converter

Color Converter

Number Base Converter

Checklists 9