This article is a contrastive study of birthday interactions in German and Chinese on WhatsApp and WeChat, respectively. The congratulatory formulas of both languages are examined, along with communicative and culture-specific phenomena related to written languages and pictograms in digital writing. This article attempts to explain the theoretical basis of general routine formulas and formulaic language, as well as greetings in messenger writing, and linguistic cultural analysis. In addition, the author has conducted an empirical investigation. At the textual level, high-frequency expressions in German and Chinese congratulatory dialogues have been collected quantitatively and presented in two word clouds. Apart from this, concrete acts of communication in both contexts will be analyzed qualitatively. The associated image-related discussion is conducted based on an overview of the general use of image symbols in messenger messages and, in particular, of the 15 emojis that are identified to be most frequently used as non-verbal components of congratulations. This is followed by examples of the use of figurative signs and a qualitative discussion of their culture-specific characteristics. This article also identifies the relationship building in birthday congratulations in Chinese WeChat and German WhatsApp. This research explains the change of the use of emojis and stickers in messenger writing and whether new communication possibilities in messenger messages can be expected in the future.
