ClickHouse Functions/Date Functions

now

Return the current server DateTime — the anchor for relative time filters.

Signature

now(): DateTime

Returns

DateTime

What it does

Returns the current server DateTime at query execution time. Used as the anchor point for relative time range filters and as a default value for inserted rows.

now() is called once per query (not once per row), making it safe and efficient for WHERE clause filtering. Combining now() with INTERVAL arithmetic covers almost all relative time window queries: last N hours, rolling 30 days, since start of today. It always returns server time — if your ClickHouse cluster is set to UTC, now() returns UTC.

Notes

  • now() is evaluated once per query, not per row — safe for partition pruning.
  • now64() provides sub-second precision (returns DateTime64).
  • today() returns just the current Date (no time); yesterday() returns yesterday's Date.
  • For reproducible tests, replace now() with a fixed timestamp.

Example SQL

now in ClickHouse SQL

now-example.sql

TypeScript with hypequery

Use now in a typed TypeScript query

hypequery gives you a type-safe query builder for ClickHouse. The generated schema maps your ClickHouse columns to TypeScript types, and raw SQL expressions let you incorporate functions like now when you need them inside a builder query.

recent-events.ts

Common questions

What developers search for with now

ClickHouse last 7 days filter

WHERE created_at >= now() - INTERVAL 7 DAY is the idiomatic ClickHouse pattern. In hypequery, pass a JavaScript Date calculated from Date.now().

ClickHouse current timestamp

now() gives you the server DateTime. now64() gives microsecond precision. today() gives just the date.

FAQ

Frequently asked questions about now

Is now() evaluated per row or per query?

Per query. It is called once when the query starts executing, so all rows in the same query see the same timestamp.

How do I get millisecond precision?

Use now64() which returns DateTime64(3) — milliseconds. Or now64(6) for microseconds.

Related functions

Functions used alongside now

Next step

Use now in a type-safe TypeScript query

hypequery generates TypeScript types from your ClickHouse schema. Use now alongside the builder, and reach for raw SQL expressions when the function is not exposed as a dedicated helper.