Verified Developer Solution • 100% OfflineFix "did not find expected key while parsing a block mapping"
Troubleshoot YAML parser errors caused by misaligned indentation or hidden tab characters.
The Problem (Error Root Cause)Exception
Your YAML parser crashes with `did not find expected key`. This almost always means your indentation levels are mixed up. A child element is indented less than or equal to its parent, breaking the block mapping.
Identified via runtime validation & stack traces
The Solution (Step-by-Step Fix)Verified
Check your indentation. YAML requires exact spaces. A common mistake is indenting a list item `-` without indenting its contents correctly.
Deterministic, non-destructive resolution
Code Standard: Bad Pattern vs Verified Fix
Live SyntaxAnti-Pattern vs Verified Fix
1# ❌ Bad: Misaligned list2steps:3- name: Build4 script: make build5 6# ✅ Good: Correct alignment7steps:8 - name: Build9 script: make buildTest and resolve this using YAML to JSON / JSON to YAML Converter
Execute directly in your browser memory. Zero API keys, zero network tracking, completely client-side.
Frequently Asked Questions
Q:Can I use a linter for this?
Yes, setting up a YAML linter in your IDE is highly recommended.
Q:How do I fix large YAML files quickly?
Paste it into our YAML to JSON converter. The error output will pinpoint the exact line number of the indentation failure.