PayloadTools
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YAML Tools

Format, beautify, minify, validate, convert, and compare YAML — directly in your browser, no signup, no upload, no install. Beautify a messy Kubernetes manifest or CI config, catch syntax errors, duplicate keys, and tab indentation with a full line/column report, fix the fixable ones with one click, convert to and from JSON or CSV with key order preserved, validate a Kubernetes manifest against its real API schema, and diff two YAML files side-by-side to spot every added, removed, or changed line. Every tool runs entirely on your device, so your data stays private and results appear instantly, even for large files.

YAML Formatter

Beautify or minify YAML instantly. Format messy YAML into readable, indented output.

Open YAML Formatter

YAML Validator

Validate YAML syntax and catch duplicate keys, tab indentation, and multi-document errors with line/column detail — then fix them with one click.

Open YAML Validator

YAML to JSON Converter

Convert YAML to JSON and JSON to YAML, bidirectionally, with key order preserved and multi-document YAML support.

Open YAML to JSON Converter

YAML Compare

Compare two YAML files side-by-side and highlight the differences.

Open YAML Compare

YAML to CSV Converter

Convert array-shaped YAML into CSV, and CSV back into YAML, bidirectionally, with dot-notation flattening and type inference.

Open YAML to CSV Converter

Kubernetes YAML Validator

Validate Kubernetes manifests against the real Kubernetes API schema for Deployment, Service, Pod, ConfigMap, and Ingress — not just generic YAML syntax.

Open Kubernetes YAML Validator

YAML Tools - When to use ?

Six focused tools, each built for a specific step in working with YAML.

YAML Formatter

Beautify or minify YAML instantly. Format messy YAML into readable, indented output.

When to use it

You have a Kubernetes manifest, Docker Compose file, or CI config with inconsistent indentation and need it readable, or need to catch a syntax error before deploying.

  • Re-indent into clean block style with 2 or 4 spaces
  • Minify into compact flow style
  • Instant syntax validation with error details
  • Handles multi-level nested config smoothly
Open YAML Formatter

YAML Validator

Validate YAML syntax and catch duplicate keys, tab indentation, and multi-document errors with line/column detail — then fix them with one click.

When to use it

You need to confirm a YAML file is correct before it ships — not just valid syntax, but free of duplicate keys and tab-indentation mistakes that a plain parser check won't catch — and fix what's fixable without leaving the page.

  • Line/column error list for every issue in one pass
  • Explicit duplicate-key detection
  • Tab-vs-space indentation detection
  • One-click auto-fix, or Fix All at once
  • Validates multi-document YAML independently
  • Copy or download a validation report
Open YAML Validator

YAML to JSON Converter

Convert YAML to JSON and JSON to YAML, bidirectionally, with key order preserved and multi-document YAML support.

When to use it

You need to move a config or payload between YAML and JSON — feeding a manifest into a JSON-only tool, or turning an API response into a hand-editable YAML file.

  • YAML → JSON and JSON → YAML from one page
  • Key order preserved in both directions
  • Multi-document YAML converts to a JSON array
  • Separate, clearly labeled error states per direction
  • Upload or download either format
Open YAML to JSON Converter

YAML Compare

Compare two YAML files side-by-side and highlight the differences.

When to use it

You're reviewing a change to a Kubernetes manifest, Docker Compose file, or CI workflow and need to see exactly what changed between two versions.

  • Side-by-side diff with added/removed highlights
  • Works with Kubernetes, Compose, Actions, and Ansible YAML
  • Validates both files before comparing
  • Paste both sides directly, no upload needed
Open YAML Compare

YAML to CSV Converter

Convert array-shaped YAML into CSV, and CSV back into YAML, bidirectionally, with dot-notation flattening and type inference.

When to use it

You have a YAML list of maps — an inventory, a user list, an Ansible variable file — and need it as a spreadsheet, or you need to turn an edited CSV back into YAML.

  • YAML → CSV and CSV → YAML from one page
  • Nested keys flattened into dot-notation columns
  • Type inference on CSV → YAML, with a toggle to disable it
  • Clear error when the YAML root isn’t a list
  • Upload or download either format
Open YAML to CSV Converter

Kubernetes YAML Validator

Validate Kubernetes manifests against the real Kubernetes API schema for Deployment, Service, Pod, ConfigMap, and Ingress — not just generic YAML syntax.

When to use it

You're about to apply a Deployment, Service, Pod, ConfigMap, or Ingress manifest and want to catch a wrong field type or missing required property before it hits the cluster.

  • Validates against real Kubernetes schemas, not just YAML syntax
  • Covers Deployment, Service, Pod, ConfigMap, and Ingress
  • Multi-document manifests validated one at a time
  • Every violation reported with its schema path and message
  • Unrecognized apiVersion/kind flagged distinctly
Open Kubernetes YAML Validator

Everything You Need to Work with YAML

One consistent toolkit for the YAML tasks developers reach for most often — all free, all client-side.

Fast Browser Processing

Every operation runs locally in JavaScript — no round trip to a server.

Data Never Leaves Your Browser

Your YAML is processed on-device and never uploaded anywhere.

Format & Beautify YAML

Re-indent messy YAML into clean, consistent block style.

Minify YAML

Collapse YAML into compact flow style using {} and [].

Validate YAML

Catch syntax errors, duplicate keys, and tab indentation with exact line/column detail.

One-Click Auto-Fix

Remove duplicate keys and convert tabs to spaces automatically, one at a time or all at once.

Convert YAML ↔ JSON

Convert bidirectionally with key order preserved and multi-document YAML support.

Convert YAML ↔ CSV

Flatten a YAML list of maps into CSV, or turn a CSV back into YAML with type inference.

Validate Kubernetes Manifests

Check a Deployment, Service, Pod, ConfigMap, or Ingress against its real Kubernetes API schema, not just YAML syntax.

Compare YAML

Diff two YAML files and see every addition, removal, and change.

Syntax Highlighting

Read and edit YAML in a full Monaco editor, the same one used in VS Code.

Copy Result

Copy formatted, minified, converted, compared, or validation report output to your clipboard in one click.

Download Result

Save output or a validation report as a standalone file for your project or docs.

What is YAML?

YAML — "YAML Ain't Markup Language" — is a human-friendly, text-based format for representing structured data, built around indentation rather than brackets or braces. First released in 2001, it has become the default configuration language for cloud-native tooling: Kubernetes, Docker Compose, GitHub Actions, Ansible, and countless CI/CD pipelines are all configured in YAML.

The format uses whitespace indentation to express nesting, a leading dash (-) for list items, and colon-separated key-value pairs for mappings — with no closing brackets required. This makes well-written YAML noticeably shorter and easier to scan than the equivalent JSON or XML, but it also means indentation errors are the most common source of broken YAML, since whitespace is meaningful rather than cosmetic.

YAML is a strict superset of JSON in most implementations — any valid JSON document is also valid YAML — while adding features JSON lacks: comments (starting with #), multi-document files separated by ---, anchors and aliases for reusing blocks, and both block style (indented, multi-line) and flow style (inline, JSON-like) for the same data.

Developers reach for YAML tooling — formatters, validators, and diff tools — because config files are usually hand-edited under time pressure, and a single misplaced space can silently change a document's meaning or break a deploy. A quick pass through a formatter or validator is a routine part of reviewing infrastructure and pipeline changes before they ship.

Where YAML Is Used

YAML powers most of the cloud-native and CI/CD tooling ecosystem.

Kubernetes Manifests

Deployments, services, and config maps are all defined in YAML.

Docker Compose

Multi-container app definitions for local dev and testing.

CI/CD Pipelines

GitHub Actions, GitLab CI, and CircleCI workflows.

Configuration Management

Ansible playbooks and roles for infrastructure automation.

Application Configs

Spring Boot, Symfony, and countless app config files.

Cloud Infrastructure

AWS CloudFormation, Serverless Framework, and IaC templates.

API Specifications

OpenAPI and Swagger specs are commonly authored in YAML.

Data Serialization

Structured config and data exchange outside the web-API context.

A Typical YAML Workflow

How these tools fit together when you're working with a real Kubernetes manifest or CI config.

  1. 1

    Receive YAML File

    Copy a raw manifest, Compose file, or CI config.

  2. 2

    Validate & Fix

    Check syntax, duplicate keys, and tab indentation, then fix the fixable ones with one click.

  3. 3

    Format

    Re-indent it into clean, consistent block style.

  4. 4

    Minify if Needed

    Collapse into compact flow style for storage or diffing.

  5. 5

    Convert if Needed

    Turn it into JSON for a JSON-only tool, or back again.

  6. 6

    Compare Changes

    Diff against a previous or expected version.

  7. 7

    Copy / Download

    Grab the result for your repo, pipeline, or docs.

Example YAML

A few common shapes of YAML you can try directly in any of the tools above.

Simple Mapping

id: 101
name: Ada Lovelace
active: true
FormatValidateConvertCompare

Nested Mapping

user:
  id: 101
  name: Ada Lovelace
  address:
    city: London
    country: UK
FormatValidateConvertCompare

List of Items

roles:
  - admin
  - editor
  - viewer
FormatValidateConvertCompare

Kubernetes-Style Config

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web
spec:
  replicas: 3
FormatValidateConvertCompare

Why PayloadTools?

Browser Processing

Every tool runs client-side, entirely on your device.

No Server Upload

Your YAML is never transmitted to or stored on a server.

Fast

Results appear instantly, even for large documents.

Free Forever

No paywalls, tiers, or usage limits.

Mobile Friendly

Fully usable on phones and tablets, not just desktop.

Unlimited Usage

No account, no rate limits, no watermarks.

Modern UI

A clean, fast interface built for daily developer use.

Frequently Asked Questions

Common questions about YAML and about these tools specifically.

Related YAML Resources

In-depth guides on YAML, coming soon.

Guide · Coming soon

YAML vs JSON

When to reach for YAML versus JSON in configs and APIs.

Guide · Coming soon

YAML Best Practices

Conventions for indentation, anchors, and structuring config files.

Guide · Coming soon

Common YAML Errors

The indentation and syntax mistakes that most often break YAML.

Guide · Coming soon

YAML Syntax Guide

A complete reference for block style, flow style, and data types.

Guide · Coming soon

How to Validate YAML

Approaches to validating YAML syntax in your CI pipeline.

Guide · Coming soon

Kubernetes YAML Guide

Structuring manifests for Deployments, Services, and ConfigMaps.