Does the match need to be exact, or does it work like a text find-and-replace?

It's an exact match against a leaf value's string form, not a substring search. A value of "staging environment" won't be touched by a search for "staging", only a value that's exactly "staging" is replaced. This avoids accidentally mangling part of a longer, unrelated string.

Does it match values of any type, not just strings?

Yes. Numbers, booleans, and `null` are compared by their string form too, so a search for "3" matches both the string `"3"` and the number `3` in the source YAML, and both get replaced.

What type does the replacement value end up as in the output?

The replacement is always inserted as a string, matching how YAML's writer serializes text you type into the replacement box. If you need the result to stay a genuine YAML number or boolean rather than a string, edit the output afterward or use YAML Quotes to Single/Double to review quoting.

Will this replace a matching key name too, or only values?

Only values. A mapping key that happens to equal the search text is left completely untouched; use YAML Key Replacer if you want to rename keys instead.

Does this tool send my YAML anywhere?

No, the replacement happens entirely client-side using the same `yaml` parser used across this category. Nothing you paste is uploaded.

Replace YAML Values - Bulk Replace a Scalar Value Online

Overview

Introduction

Bulk-updating a repeated value across a YAML config, an environment name, a hostname, a version tag, by hand is tedious and risks missing an occurrence buried in a nested section. This tool replaces every exact match in one pass.

Because it works structurally against parsed leaf values rather than raw text, it never mangles a substring inside a longer, unrelated value the way a naive text find-and-replace could.

What Is YAML Value Replacer?

A YAML value replacer that walks a parsed document and, wherever it finds a leaf scalar value exactly equal to the old value (compared as text), replaces it with the new value, everywhere it occurs.

The result is re-serialized as clean, block-style YAML using the same writer as this category's YAML Formatter.

How YAML Value Replacer Works

The input is parsed with a full YAML 1.2 parser into a plain JS value, then rebuilt recursively: every leaf scalar is compared, as its string form, against the old value, and swapped for the replacement text on an exact match. Objects and arrays are walked but never treated as matchable values themselves.

The rebuilt value is then re-serialized as block-style YAML, so the output stays valid, correctly quoted YAML regardless of what characters the replacement text contains.

When To Use YAML Value Replacer

Use it to bulk-update a setting, like changing every `env: staging` to `env: production`, across a large document in one operation.

It's also useful for scrubbing a specific value (a placeholder, a stale identifier) that's repeated in several places before sharing a config.

Often used alongside YAML Value Extractor, YAML Value Finder and YAML Key Replacer.

Features

Advantages

Replaces every occurrence in one pass, eliminating the risk of missing an instance by hand.
Exact-match comparison means it never partially mangles a longer string that happens to contain the search text.
Guarantees valid YAML output, since the replacement value is inserted through the parser's own writer, not raw text splicing.
Runs entirely client-side, so configuration data never leaves your browser.

Limitations

Matching is exact, not a substring or pattern match, a value that only partially matches the search text is left untouched by design.
The replacement is always inserted as a string; genuinely numeric or boolean replacements need a manual edit afterward if the distinction matters.
Re-serializing normalizes layout (flow style becomes block style, indentation is standardized), the same side effect as this category's other parse-and-reserialize tools.

Examples

Replacing a repeated value

Input

env: staging
service:
  env: staging

Output

env: production
service:
  env: production

Both leaf values exactly equal to "staging" are replaced with "production", wherever they occur.

Best Practices & Notes

Best Practices

Search with YAML Value Finder first to confirm exactly which and how many values will be affected before replacing.
Diff the output against the original with YAML Diff to confirm only the intended values changed.
For a numeric or boolean replacement, double-check the output's quoting afterward, since replacements are inserted as text.

Developer Notes

The replacer recursively rebuilds objects and arrays untouched, converting only genuine leaf scalars to their string form for an exact `===`-style comparison against the search text before substitution. This mirrors the exact-match semantics of this site's XML Value Replacer's approach conceptually, adapted for YAML's typed scalar model rather than XML's plain text nodes.

YAML Value Replacer Use Cases

Bulk-updating an environment name, hostname, or version string repeated across a config
Scrubbing a stale placeholder value before sharing a document externally
Standardizing an inconsistent value (like mixed casing of a status string) across a large file
Preparing a config for a new environment by swapping every occurrence of an old setting

Common Mistakes

Expecting a substring match; the tool only replaces values that exactly equal the search text.
Assuming a numeric replacement stays a number in the output; replacements are always inserted as text.
Confusing this with a key rename, this tool only touches values, use YAML Key Replacer for key names.

Tips

Use YAML Value Finder beforehand to preview exactly which values will be affected.
Chain into YAML Diff afterward to visually confirm the change matches your expectations.
For a key rename instead of a value change, use YAML Key Replacer.

YAML Value Replacer