Port Zero vs CurlyJSON

A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.

Port Zero compared with CurlyJSON
Detail	Port Zero	CurlyJSON
What it does	Stable domains for local development ports, eliminating conflicts with free open-source tunnels and paid cloud options	JSON Formatter & Validator — Free, Private & Offline
Stage	Not given	Not given
Founded	Not given	Not given
Based in	Not given	Not given
Pricing model	Freemium	Freemium
Pricing	Free and Open Source: $0 (unlimited local tunnels, open source); Professional: $49/mo or $490/yr (unlimited cloud tunnels, visitor auth, feedback comments); Team: $149/mo or $1,490/yr (everything in Professional plus unlimited members, teams, shared subdomains, approvals, organization billing); Ente	Free for all tools. Pro: $29.99 per year or $4 per month, plus tax.
Key features	Stable local domains (.portzero.local) for processes and containers Cloud tunnels (.tunnel.portzero.cloud) with HTTPS for LAN and internet access Support for multiple programming languages Git worktree support with per-branch URLs AI agent integration with MCP server Visitor authentication and access control Feedback comments on live tunnels Team access policies and approvals Audit log (Enterprise plan) Organization billing with no per-seat charges	Validate JSON with precise line and column errors Repair invalid JSON fixing trailing commas, quotes, and comments Preserve large integers without rounding Detect and mask API keys, tokens and passwords
What makes it different	Eliminates port conflicts by assigning stable virtual domains instead of port numbers Free and open source for local use; no additional cost for cloud features on paid plans Flat pricing with no meters, overages, or per-seat charges Agent-ready with native MCP server integration for AI coding agents Works across multiple OS and languages with zero port bookkeeping required	Keeps large numbers exactly as written instead of silently rounding them like most online formatters All free tools run entirely in your browser, working offline without uploading data Automatically detects and warns about secrets like API keys and passwords
Free plan	Not given	Not given
Open source	Not given	Not given
Platforms	Not given	Not given
Public API	Not given	Not given
Community votes	0	0
DR (Domain Rating by Ahrefs)	1 no change since last check	Not checked yet no change since last check
Trust Flow (Majestic)	4	7
Citation Flow (Majestic)	26	13
Referring domains (Majestic)	135	2

5 details filled in for both companies.

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