Free developer tools
Small, single-purpose utilities for jobs that are otherwise done by hand. Each one runs entirely in your browser: nothing you paste is uploaded, stored, or sent to a server.
AI & LLM
OpenAI Structured Outputs JSON Schema Converter
Paste any JSON Schema and get one OpenAI accepts with strict: true — additionalProperties, required and unsupported keywords fixed everywhere, plus ready-to-run Python and TypeScript.
App Store & ASO
App Store Keyword Field Deduplicator
Strip words Apple already indexes from your app name, subtitle and categories, fold plural duplicates, and see exactly how much of the 100-character keyword field you just got back.
Etsy & Marketplaces
Etsy Tag 20 Character Limit Tool
Paste tags that blow Etsy's 20-character limit and get them repacked on word boundaries — your words, your order, never cut mid-word — with the 13-slot count and a line ready for the listing editor.
a conversion or transformation BETWEEN two specific things where no clean single-purpose tool exists yet
Gcode to SVG Converter
Strong niche search intent from CNC machinists, laser engraver users, and pen plotter hobbyists needing to reverse-engineer toolpaths into scalable 2D vector graphics.
tools for an AI-era workflow gap (prompt/context/token/dataset wrangling, model-output cleanup, JSON-schema fixing) that people currently do by hand
Openai Fine Tuning Jsonl Validator
Moderate-to-high niche search volume driven by developers getting opaque validation errors when submitting OpenAI fine-tuning jobs.
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