JSON Merge & Clean
Deep merge · Remove empty · Dedupe
Merge & Clean
Ready
ABOUT
About JSON Merge & Clean
Deep-merge two JSON objects or strip null, empty strings, and other invalid fields to simplify configs and logs.
Config management, feature-flag merges, and multi-environment defaults—deep merge is a daily task in microservices and frontend apps. Merging locally lets you preview the final config before commit and avoid accidental overrides in production.
DEEP DIVE
Learn more about JSON Merge & Clean
In microservices, config often spans multiple JSON files; aggregated logs also need null and empty fields removed to shrink payload size. JSONSort merge & clean offers deep merge and one-click cleanup—both locally.
Deep merge follows last-wins semantics: nested objects merge recursively instead of being replaced wholesale—ideal for defaults + overrides.
Merge behavior is similar to lodash merge: objects recurse, scalars and arrays are replaced by the right-hand side. Know this before you merge—if you need array concat, handle it in app code or a custom strategy. Cleanup mode suits log redaction and API response slimming.
FEATURES
Core capabilities
Deep merge
Recursively merge two JSON objects so nested levels stack correctly instead of full replacement.
One-click cleanup
Remove null, empty strings, empty arrays, and empty objects.
Dual-pane input
Primary JSON on the left, merge source on the right—clear and direct.
Merge preview
Live merged output; edits on either side refresh instantly.
Formatted output
Results are pretty-printed for copy-paste use.
Local processing
Configs and logs never upload—suited for private networks.
Live preview
Any edit refreshes the merge result—great for iterating on overrides.
Cleanup stats
See size change after cleanup to gauge log compression gains.
HOW TO USE
How to use
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1
Put primary JSON on the left, merge source on the right
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2
Choose merge or cleanup mode
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3
Copy the processed JSON
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4
Adjust indent, JSON5, sort, and other advanced options in the toolbar
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5
Copy results or continue with Diff, path query, and other tools
WORKFLOW
Typical workflow
End-to-end flow from import to export so teams use JSON Merge & Clean consistently.
Prepare baseline and delta
Left: default / production baseline; right: environment override or new fragment.
Pick a mode
Use merge to stack config; use cleanup to slim JSON.
Review output
Diff before/after merge to confirm nothing was overwritten unexpectedly.
Export & deploy
Copy results to your config center or Git repo and follow your normal release process.
USE CASES
Use cases
Backend developers
Merge defaultConfig.json with environment override configs.
DevOps
Strip empty fields from alert JSON to reduce log storage size.
Frontend developers
Merge multiple Mock data sources into a single test JSON.
Data engineering
Remove null placeholders from JSON records during ETL preprocessing.
Platform engineering
Merge feature-flag JSON fragments contributed by multiple teams.
Support tooling
Clean null fields from user event JSON for easier display.
TIPS
Tips
- Format both JSON sides before merging to confirm structure matches expectations.
- Array fields are replaced wholesale by default—not merged element-by-element. Keep that in mind.
- Cleanup mode is ideal for stripping null values from many optional fields in API responses.
- Use the Diff tool to compare merge results with the original and catch unexpected overwrites.
- For large JSON merges, back up the original file first and overwrite only after verification.
- Cleaned JSON is usually better suited for database storage or downstream services.
- Merge order matters: the right side overwrites same-name fields on the left—plan defaults vs overrides accordingly.
- Diff a backup before cleanup to avoid accidentally removing empty strings the business still needs.
- After merging feature-flag JSON, format and sort before committing to storage.
- When nesting exceeds 10 levels, use the mind map to skim the merged structure first.
LOCAL VS ONLINE
Local vs online tools
JSONSort stays purely frontend—this comparison shows why local tools fit dev data better.
TROUBLESHOOTING
Common pitfalls & fixes
Issues you may hit in practice and how to handle them—save time on trial and error.
Array shorter/longer after merge
Tip:Whole-array replacement is expected; append manually if you need concatenation.
Cleanup removed "0" or false
Tip:Cleanup keeps 0 and false; if missing, check for null or "".
Merge result unexpected
Tip:Check key spelling differences (camelCase vs snake_case) that prevented merging.
Types differ on each side
Tip:Same key as object on one side and string on the other overwrites directly—unify types first.
FAQ
FAQ
Are arrays appended or replaced?
Replaced wholesale by default. If the right side has an array field, it fully overwrites the left same-name field.
Does cleanup remove false and 0?
No. Only null, "", [], {} and similar empties—false, 0, and other valid falsy values are kept.
Can I merge more than two JSON files?
Currently dual-pane. Merge the first two, then merge that result with the third.
Does merge change the original input?
No. Only the output area shows results; left-side input stays unchanged.
Does cleanup recurse into nested objects?
Yes. null, "", [], {} at every level are cleaned recursively.
Is data uploaded to a server?
No. All JSONSort tools run locally in your browser—your input is never sent to any backend.
Do I need to sign up or install anything?
No. Open the page and go—no account, no client download, PWA offline cache supported.
How large can files be?
Depends on browser memory; multi-MB data usually runs smoothly. Split very large files or use merge & clean first.