Compare Union Alpha from Stealth and GLM 5.3 Flash from Z.ai on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the OpenRouter API.
Union Alpha and GLM 5.3 Flash are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Union Alpha, from Stealth, has a 262,144-token context window and is free to use on OpenRouter.
GLM 5.3 Flash, from Z.ai, has a 1,310,720-token context window and is priced at $0.075/M tokens input, $0.25/M tokens output on OpenRouter.