MuleSoft DataWeave Date Time Formatting

Question

Using input payload of

{
"Date": "2025年09月09日T18:03:06.830"
}

I'm trying to get an output of

"2025年09月09日T18:03:06.830Z"

I've tried this DataWeave

%dw 2.0
output application/json
---
payload.Date as String {format: "yyyy-MM-dd'T'HH:mm:ss.SSSZ"}

But my output is coming back as

"2025年09月09日T18:03:06.830"

Without the Z at the end of the milliseconds

I've also tried

%dw 2.0
output application/json
---
payload.Date as String {format: "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"}

With no luck

I can't seem to find as DateTime formatting that is helping me either. I've also found outputs with 2 milliseconds and a Z but not 3 (such as the basic payload.Date as DateTime output)

• aled: This question is similar to: Dataweave Date Formatting with Timezone. If you believe it’s different, please edit the question, make it clear how it’s different and/or how the answers on that question are not helpful for your problem.

Answer 1

Interesting find, so if I use

(payload.Date as DateTime) as String {format: "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"}

I get the string that I'm looking for.

A couple of conversions, but it gets the job done.

• aled: They are not additional conversions. The date/time formatting only makes sense when converting from/to Date/Time types and String. String or Date/Times don't have formats in DataWeave, like Java. The input here is a String and the output is a String. You need to convert to a Date/Time type first to change the output format.