Jsonlint
Worth it
Confidence: High
Buy . it's free: JSONLint is the classic paste-and-validate tool for quick JSON fixes.
New check
Comparison
Jsonlint vs JsonFormatter
Jsonlint lands on Worth it, and JsonFormatter lands on Skip.
JsonFormatter
Skip
Confidence: Medium
Only acceptable for non-sensitive JSON you would not mind publishing; its paste URLs exposed thousands of passwords and API keys over roughly seven years.
| Compare | ||
|---|---|---|
| Verdict | Worth it | Skip |
| Best for | Devs debugging API payloads | Formatting non-sensitive sample payloads |
| Who it's not for | Anyone with confidential or production data . never paste it into online validators | Anyone pasting API keys, tokens, or credentials |
| Privacy | No website breaches found; the npm jsonlint package has known high-severity CVEs, and the site publishes its own security page.⁹ | Poor: researchers disclosed years of publicly readable user pastes containing passwords and API keys (Nov 2025).14 |
| Support quality | No evidence of any support channel. | No support evidence in sources |
| Public sentiment | A long-standing default for quick JSON checks; users call it easy, though 2026 comparisons list many richer alternatives.⁵ | User-review coverage is thin and dominated by the November 2025 leak reporting; no substantive verbatim user quotes surfaced. |
| Biggest gotcha | Online validators are a known leak vector . no data protection guarantees.11 | Anything you pasted was potentially publicly readable; rotate any keys or passwords sent through it14 |
Pick Jsonlint when
- Devs debugging API payloads
- Quick one-off JSON checks
- Formatting minified JSON
- Students learning JSON syntax
When Jsonlint is not a fit
- Anyone with confidential or production data . never paste it into online validators
- CI/CD pipelines needing automated, repeatable linting
- Teams wanting schema validation or auto-repair
- Anyone expecting support, SLAs, or vendor accountability
Pick JsonFormatter when
- Formatting non-sensitive sample payloads
- Quick browser validation
- One-off checks and learning
When JsonFormatter is not a fit
- Anyone pasting API keys, tokens, or credentials
- Teams handling customer PII or regulated data
- Companies with vendor security review requirements
- Privacy-conscious developers; local tools are equally free
Sources
- JSONLint - The JSON Validatorjsonlint.comofficial
- Source code for jsonlint.comgithub.comofficial
- JSONLint error code E001jsonlint.comofficial
- JSONLint comments documentationjsonlint.comofficial
- Free no-signup tools list (Reddit)reddit.comreview
- 5 Best JSON Formatter Online Toolshypertest.coreview
- Best Free JSON Formatters Comparedtoolbox-kit.comreview
- JSONLint 2026 Reviewaijet.ccreview
- CVE-2022-42227: jsonlint 1.0 heap-buffer overflowbreachspider.comsecurity
- CVE-2021-23358 in underscore 1.6.0github.comsecurity
- Is Your Data Safe When Using Online JSON Validators?inventivehq.comreview
- BidTune ad revenue case studybidtune.comnews
- JSON Formatter (official site)jsonformatter.orgofficial
- Thousands of Secrets Leaked on Code Formatting Platformssecurityweek.comnews
- Cloud tools JSONFormatter and CodeBeautify quietly leaked thousands of passwords and API keysblog.intelligencex.orgsecurity
- Seven Years on a Public Clipboard: Pasted Secretsbeyondmemory.iosecurity