Remember JSON Formatter? The Chrome extension with 200K+ users that auto-formatted JSON in your browser? In mid-2026 it went closed-source, partnered with GiveFreely, and started injecting geolocation tracking plus donation popups into checkout pages. The developer's defense was "it's for charity." The community's response was a collective "uninstall immediately." This incident left a gaping hole in many developers' toolchains, forcing a rapid search for reliable, trustworthy replacements. As developers, we live and breathe JSON. API responses, configuration files, logs, and data payloads all rely on this ubiquitous format. Losing a trusted tool means re-evaluating our entire workflow. This article dives into the performance, features, and security of the leading contenders that emerged from the ashes of the JSON Formatter scandal.
The Contenders: Beyond the Scandal
The fallout from the JSON Formatter incident was swift. Developers, burned by a tool they relied on daily, scoured the internet for alternatives. The criteria were clear: open-source, actively maintained, and free from invasive tracking or unexpected monetization. We evaluated several prominent options, focusing on their core functionality, usability, and adherence to developer best practices. This wasn't just about finding a replacement; it was about rebuilding trust in our tooling.
JSON Formatter (arnav-kr) — The Spiritual Successor
This is the most popular open-source fork of the original. It boasts over 60 themes, a collapsible toolbar, and extensive keyboard shortcuts for nearly every action. Its strength lies in its commitment to being truly open-source and actively maintained. It works offline, a crucial feature for many development environments, and its free tier is remarkably generous. However, it struggles with large files; anything above ~5MB becomes sluggish. It also lacks built-in JWT decoding and advanced export options, which are becoming increasingly standard in modern JSON viewers.
Pros:
- Truly open source and actively maintained.
- Extensive theming and keyboard shortcuts.
- Works offline.
- Generous free tier.
Cons:
- Struggles with large files (above ~5MB).
- No JWT decoding.
- Limited advanced export features.
JSON Viewer (krispo)
Another strong contender, krispo's JSON Viewer offers a clean, intuitive interface. It supports large files much better than arnav-kr's fork, handling files upwards of 50MB without significant performance degradation. It includes JWT decoding, syntax highlighting, and a copy-to-clipboard function. The extension is lightweight and doesn't hog browser resources. Its primary limitation is a less extensive theming engine compared to some competitors, and it lacks advanced features like custom export formats or data filtering. It is, however, a solid, reliable choice for everyday JSON viewing.
Pros:
- Excellent performance with large files (up to 50MB+).
- Built-in JWT decoding.
- Clean and intuitive UI.
- Lightweight.
Cons:
- Limited theming options.
- Lacks advanced export and filtering.
JSONView (JSONView)
JSONView, often confused with other similarly named extensions, is a seasoned veteran. It focuses on speed and simplicity. It renders JSON directly in the browser and offers basic formatting and collapsing of nodes. Its main advantage is its speed and minimal footprint. It's ideal for quickly inspecting API responses without any fuss. However, it lacks many of the quality-of-life features found in newer extensions, such as extensive theming, JWT decoding, or robust handling of extremely large files. For developers who prioritize raw speed and a no-frills experience, JSONView remains a viable option.
Pros:
- Extremely fast and lightweight.
- Simple, direct rendering.
- Minimal browser resource usage.
Cons:
- Basic formatting only.
- No JWT decoding.
- Poor handling of very large files.
- Limited customization.
JSON Editor Online (MyJSONEditor.com)
Moving beyond browser extensions, online tools offer a different approach. MyJSONEditor.com provides a web-based interface that includes a JSON viewer, editor, and validator. It handles very large files with ease, thanks to its server-side processing. It offers a powerful editor with auto-completion, syntax checking, and reformatting capabilities. It also supports exporting in various formats. The main drawback is the reliance on an internet connection and the fact that sensitive data must be uploaded to a third-party server, which can be a security concern for some organizations. For quick, powerful editing and viewing without installing anything, it's a strong choice, provided security policies allow.
Pros:
- Powerful editor with auto-completion and validation.
- Handles extremely large files.
- Supports various export formats.
- No installation required.
Cons:
- Requires an internet connection.
- Data uploaded to a third-party server raises security concerns.
The Unanswered Question: Trust and Transparency
The JSON Formatter scandal wasn't just about a tool breaking; it was about a breach of trust. Developers placed their faith in an extension, and that faith was exploited. This raises a critical, unanswered question: How can developers ensure the integrity of their essential tooling in an ecosystem where popular extensions can pivot to malicious behavior overnight? While open-source forks and active maintenance are positive indicators, they don't entirely eliminate the risk. The ease with which the original JSON Formatter shifted its behavior highlights the inherent vulnerability of relying on third-party browser add-ons for critical tasks. What mechanisms can be put in place, either by browser vendors or the developer community, to provide greater assurance of a tool's continued benign nature after installation?
What This Means for Your Workflow
The search for a reliable JSON viewer is now a critical part of maintaining a secure and efficient development workflow. The incident with JSON Formatter serves as a stark reminder to regularly audit your installed extensions and to prioritize tools with transparent development practices and a clear commitment to open-source principles. For developers who regularly handle large JSON payloads, prioritizing viewers like krispo's JSON Viewer or online tools like MyJSONEditor.com (with appropriate security considerations) is essential. Those who need quick, basic inspection might still find value in older, simpler tools like JSONView. The key is to choose a tool that balances functionality with trustworthiness, ensuring your development environment remains a secure space for handling sensitive data.