Translation guide
Expresses gradual change or a daily routine. The most natural Japanese depends on whether you mean 'little by little over time' or 'each day as it comes'.
Describing something that changes or develops slowly, step by step, each day.
The most common and natural way to say 'day by day' for gradual change. Works in both spoken and written Japanese.
日々成長している。
I'm growing day by day.
The situation changes day by day.
Emphasizes a noticeable change occurring each day. Often used with verbs like 増える (increase) or 良くなる (get better).
It's getting colder day by day.
His Japanese is improving day by day.
Literally 'one day, one day', emphasizing each individual day's contribution to progress or change.
Live each day as it comes, day by day.
Focusing on each day individually, often in the context of living or working without worrying about the future.
日々 is more general and can be used for both gradual change and daily routine. 日に日に specifically highlights a noticeable change happening each day, often with a sense of progression.
recover day by day
I'm just struggling to get by day by day.