Timestamp functions

Timestamp Functions

Name Description
CURRENT_TIMESTAMP Generates a TIMESTAMP corresponding to the request time.
TIMESTAMP_TRUNC Truncates a TIMESTAMP to a given granularity.
UNIX_MICROS_TO_TIMESTAMP Converts the number of microseconds since 1970-01-01 00:00:00 UTC to a TIMESTAMP
UNIX_MILLIS_TO_TIMESTAMP Converts the number of milliseconds since 1970-01-01 00:00:00 UTC to a TIMESTAMP
UNIX_SECONDS_TO_TIMESTAMP Converts the number of seconds since 1970-01-01 00:00:00 UTC to a TIMESTAMP
TIMESTAMP_ADD Adds a time interval to a TIMESTAMP
TIMESTAMP_SUB Subtracts a time interval to a TIMESTAMP
TIMESTAMP_TO_UNIX_MICROS Converts a TIMESTAMP to the number of microseconds since 1970-01-01 00:00:00 UTC
TIMESTAMP_TO_UNIX_MILLIS Converts a TIMESTAMP to the number of milliseconds since 1970-01-01 00:00:00 UTC
TIMESTAMP_TO_UNIX_SECONDS Converts a TIMESTAMP to the number of seconds since 1970-01-01 00:00:00 UTC

CURRENT_TIMESTAMP

Syntax:

current_timestamp() -> TIMESTAMP

Description:

Gets the timestamp at the beginning of request time input (interpreted as the number of microseconds since 1970-01-01 00:00:00 UTC).

This is stable within a query, and will always resolve to the same value if called multiple times.

TIMESTAMP_TRUNC

Syntax:

timestamp_trunc(timestamp: TIMESTAMP, granularity: STRING[, timezone: STRING]) -> TIMESTAMP

Description:

Truncates a timestamp down to a given granularity.

The granularity argument must be a string and one of the following:

  • microsecond
  • millisecond
  • second
  • minute
  • hour
  • day
  • week
  • week([weekday])
  • month
  • quarter
  • year
  • isoyear

If the timezone argument is provided, truncation will be based on the given timezone's calendar boundaries (e.g. day truncation will truncate to midnight in the given timezone). The truncation will respect daylight savings time.

If timezone is not provided, truncation will be based on UTC calendar boundaries.

The timezone argument should be a string representation of a timezone from the tz database, for example America/New_York. A custom time offset can also be used by specifying an offset from GMT.

Examples:

timestamp granularity timezone timestamp_trunc(timestamp, granularity, timezone)
2000-01-01 10:20:30:123456 UTC "second" Not provided 2001-01-01 10:20:30 UTC
1997-05-31 04:30:30 UTC "day" Not provided 1997-05-31 00:00:00 UTC
1997-05-31 04:30:30 UTC "day" "America/Los_Angeles" 1997-05-30 07:00:00 UTC
2001-03-16 04:00:00 UTC "week(friday) Not provided 2001-03-16 00:00:00 UTC
2001-03-23 04:00:00 UTC "week(friday) "America/Los_Angeles" 2001-03-23 17:00:00 UTC
2026-01-24 20:00:00 UTC "month" "GMT+06:32:43" 2026-01-01T06:32:43 UTC

UNIX_MICROS_TO_TIMESTAMP

Syntax:

unix_micros_to_timestamp(input: INT64) -> TIMESTAMP

Description:

Converts input (interpreted as the number of microseconds since 1970-01-01 00:00:00 UTC) to a TIMESTAMP. Throws an error if input cannot be converted to a valid TIMESTAMP.

Examples:

input unix_micros_to_timestamp(input)
0L 1970-01-01 00:00:00 UTC
400123456L 1970-01-01 00:06:40.123456 UTC
-1000000L 1969-12-31 23:59:59 UTC
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("createdAtMicros").unixMicrosToTimestamp().as("createdAtString")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("createdAtMicros").unixMicrosToTimestamp().as("createdAtString")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("createdAtMicros").unixMicrosToTimestamp().as("createdAtString")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAtMicros").unixMicrosToTimestamp().alias("createdAtString")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAtMicros").unixMicrosToTimestamp().alias("createdAtString")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(
        Field.of("createdAtMicros")
        .unix_micros_to_timestamp()
        .as_("createdAtString")
    )
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(unixMicrosToTimestamp(field("createdAtMicros")).as("createdAtString"))
        .execute()
        .get();

UNIX_MILLIS_TO_TIMESTAMP

Syntax:

unix_millis_to_timestamp(input: INT64) -> TIMESTAMP

Description:

Converts input (interpreted as the number of milliseconds since 1970-01-01 00:00:00 UTC) to a TIMESTAMP. Throws an error if input cannot be converted to a valid TIMESTAMP.

Examples:

input unix_millis_to_timestamp(input)
0L 1970-01-01 00:00:00 UTC
4000123L 1970-01-01 01:06:40.123 UTC
-1000000L 1969-12-31 23:43:20 UTC
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("createdAtMillis").unixMillisToTimestamp().as("createdAtString")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("createdAtMillis").unixMillisToTimestamp().as("createdAtString")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("createdAtMillis").unixMillisToTimestamp().as("createdAtString")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAtMillis").unixMillisToTimestamp().alias("createdAtString")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAtMillis").unixMillisToTimestamp().alias("createdAtString")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(
        Field.of("createdAtMillis")
        .unix_millis_to_timestamp()
        .as_("createdAtString")
    )
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(unixMillisToTimestamp(field("createdAtMillis")).as("createdAtString"))
        .execute()
        .get();

UNIX_SECONDS_TO_TIMESTAMP

Syntax:

unix_seconds_to_timestamp(input: INT64) -> TIMESTAMP

Description:

Converts input (interpreted as the number of seconds since 1970-01-01 00:00:00 UTC) to a TIMESTAMP. Throws an error if input cannot be converted to a valid TIMESTAMP.

Examples:

input unix_seconds_to_timestamp(input)
0L 1970-01-01 00:00:00 UTC
60L 1970-01-01 00:01:00 UTC
-300L 1969-12-31 23:55:00 UTC
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("createdAtSeconds").unixSecondsToTimestamp().as("createdAtString")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("createdAtSeconds").unixSecondsToTimestamp().as("createdAtString")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("createdAtSeconds").unixSecondsToTimestamp().as("createdAtString")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAtSeconds").unixSecondsToTimestamp().alias("createdAtString")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAtSeconds").unixSecondsToTimestamp().alias("createdAtString")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(
        Field.of("createdAtSeconds")
        .unix_seconds_to_timestamp()
        .as_("createdAtString")
    )
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(unixSecondsToTimestamp(field("createdAtSeconds")).as("createdAtString"))
        .execute()
        .get();

TIMESTAMP_ADD

Syntax:

timestamp_add(timestamp: TIMESTAMP, unit: STRING, amount: INT64) -> TIMESTAMP

Description:

Adds an amount of unit from timestamp. The amount argument can be negative, in that case it is equivalent to TIMESTAMP_SUB.

The unit argument must be a string and one of the following:

  • microsecond
  • millisecond
  • second
  • minute
  • hour
  • day

Throws an error if the resulting timestamp does not fit within the TIMESTAMP range.

Examples:

timestamp unit amount timestamp_add(timestamp, unit, amount)
2025-02-20 00:00:00 UTC "minute" 2L 2025-02-20 00:02:00 UTC
2025-02-20 00:00:00 UTC "hour" -4L 2025-02-19 20:00:00 UTC
2025-02-20 00:00:00 UTC "day" 5L 2025-02-25 00:00:00 UTC
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("createdAt").timestampAdd("day", 3653).as("expiresAt")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("createdAt").timestampAdd("day", 3653).as("expiresAt")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("createdAt").timestampAdd(3653, .day).as("expiresAt")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAt")
          .timestampAdd("day", 3653)
          .alias("expiresAt")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("createdAt").timestampAdd("day", 3653).alias("expiresAt")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(Field.of("createdAt").timestamp_add("day", 3653).as_("expiresAt"))
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(timestampAdd(field("createdAt"), "day", 3653).as("expiresAt"))
        .execute()
        .get();

TIMESTAMP_SUB

Syntax:

timestamp_sub(timestamp: TIMESTAMP, unit: STRING, amount: INT64) -> TIMESTAMP

Description:

Subtracts an amount of unit from timestamp. The amount argument can be negative, in that case it is equivalent to TIMESTAMP_ADD.

The unit argument must be a string and one of the following:

  • microsecond
  • millisecond
  • second
  • minute
  • hour
  • day

Throws an error if the resulting timestamp does not fit within the TIMESTAMP range.

Examples:

timestamp unit amount timestamp_sub(timestamp, unit, amount)
2026-07-04 00:00:00 UTC "minute" 40L 2026-07-03 23:20:00 UTC
2026-07-04 00:00:00 UTC "hour" -24L 2026-07-05 00:00:00 UTC
2026-07-04 00:00:00 UTC "day" 3L 2026-07-01 00:00:00 UTC
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("expiresAt").timestampSubtract("day", 14).as("sendWarningTimestamp")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("expiresAt").timestampSubtract("day", 14).as("sendWarningTimestamp")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("expiresAt").timestampSubtract(14, .day).as("sendWarningTimestamp")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("expiresAt")
          .timestampSubtract("day", 14)
          .alias("sendWarningTimestamp")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("expiresAt").timestampSubtract("day", 14).alias("sendWarningTimestamp")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(
        Field.of("expiresAt")
        .timestamp_subtract("day", 14)
        .as_("sendWarningTimestamp")
    )
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(timestampSubtract(field("expiresAt"), "day", 14).as("sendWarningTimestamp"))
        .execute()
        .get();

TIMESTAMP_TO_UNIX_MICROS

Syntax:

timestamp_to_unix_micros(input: TIMESTAMP) -> INT64

Description:

Converts input to the number of microseconds since 1970-01-01 00:00:00 UTC. Truncates higher levels of precision by rounding down to the beginning of the microsecond.

Examples:

input timestamp_to_unix_micros(input)
1970-01-01 00:00:00 UTC 0L
1970-01-01 00:06:40.123456 UTC 400123456L
1969-12-31 23:59:59 UTC -1000000L
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("dateString").timestampToUnixMicros().as("unixMicros")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("dateString").timestampToUnixMicros().as("unixMicros")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("dateString").timestampToUnixMicros().as("unixMicros")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("dateString").timestampToUnixMicros().alias("unixMicros")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("dateString").timestampToUnixMicros().alias("unixMicros")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(Field.of("dateString").timestamp_to_unix_micros().as_("unixMicros"))
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(timestampToUnixMicros(field("dateString")).as("unixMicros"))
        .execute()
        .get();

TIMESTAMP_TO_UNIX_MILLIS

Syntax:

timestamp_to_unix_millis(input: TIMESTAMP) -> INT64

Description:

Converts input to the number of milliseconds since 1970-01-01 00:00:00 UTC. Truncates higher levels of precision by rounding down to the beginning of the millisecond.

Examples:

input timestamp_to_unix_millis(input)
1970-01-01 00:00:00 UTC 0L
1970-01-01 01:06:40.123 UTC 4000123L
1969-12-31 23:43:20 -1000000L
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("dateString").timestampToUnixMillis().as("unixMillis")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("dateString").timestampToUnixMillis().as("unixMillis")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("dateString").timestampToUnixMillis().as("unixMillis")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("dateString").timestampToUnixMillis().alias("unixMillis")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("dateString").timestampToUnixMillis().alias("unixMillis")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(Field.of("dateString").timestamp_to_unix_millis().as_("unixMillis"))
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(timestampToUnixMillis(field("dateString")).as("unixMillis"))
        .execute()
        .get();

TIMESTAMP_TO_UNIX_SECONDS

Syntax:

timestamp_to_unix_seconds(input: TIMESTAMP) -> INT64

Description:

Converts input to the number of seconds since 1970-01-01 00:00:00 UTC. Truncates higher levels of precision by rounding down to the beginning of the second.

Examples:

input timestamp_to_unix_seconds(input)
1970-01-01 00:00:00 UTC 0L
1970-01-01 00:01:00 UTC 60L
1969-12-31 23:55:00 UTC -300L
Node.js
const result = await db.pipeline()
  .collection("documents")
  .select(
    field("dateString").timestampToUnixSeconds().as("unixSeconds")
  )
  .execute();

Web

const result = await execute(db.pipeline()
  .collection("documents")
  .select(
    field("dateString").timestampToUnixSeconds().as("unixSeconds")
  )
);
Swift
let result = try await db.pipeline()
  .collection("documents")
  .select([
    Field("dateString").timestampToUnixSeconds().as("unixSeconds")
  ])
  .execute()

Kotlin

val result = db.pipeline()
    .collection("documents")
    .select(
        field("dateString").timestampToUnixSeconds().alias("unixSeconds")
    )
    .execute()

Java

Task<Pipeline.Snapshot> result = db.pipeline()
    .collection("documents")
    .select(
        field("dateString").timestampToUnixSeconds().alias("unixSeconds")
    )
    .execute();
Python
from google.cloud.firestore_v1.pipeline_expressions import Field

result = (
    client.pipeline()
    .collection("documents")
    .select(Field.of("dateString").timestamp_to_unix_seconds().as_("unixSeconds"))
    .execute()
)
Java
Pipeline.Snapshot result =
    firestore
        .pipeline()
        .collection("documents")
        .select(timestampToUnixSeconds(field("dateString")).as("unixSeconds"))
        .execute()
        .get();