Epoch time is another name for Unix time. The "epoch" is the reference point: January 1, 1970 at 00:00:00 UTC. All Unix timestamps count seconds (or milliseconds) from that moment.

How do I convert a Unix timestamp to a date in Python?

Use datetime.datetime.fromtimestamp(ts, tz=datetime.timezone.utc) for a UTC datetime, or datetime.datetime.utcfromtimestamp(ts) for a naive UTC datetime. In Pandas, use pd.to_datetime(series, unit="s").

What is the Unix timestamp for January 1 2000?

The Unix timestamp for January 1, 2000 00:00:00 UTC is 946684800.

Why do developers use Unix timestamps?

Unix timestamps are timezone-independent integers — they sort correctly, compare easily, and are compact to store. Databases, APIs, and log systems use them to avoid ambiguity from daylight saving time and locale-specific date formats.

Unix Timestamp & Epoch Converter

Q: What is a Unix timestamp?

A Unix timestamp (also called epoch time) is the number of seconds that have elapsed since January 1, 1970 00:00:00 UTC. It is a standard way to represent a single point in time as an integer, independent of time zones.

Convert between Unix timestamps and human-readable dates. Copy-paste Python, JavaScript, and Pandas code snippets below.

Current Unix Timestamp (seconds)

1785241652

Unix timestamp (seconds or ms)

Python Code Snippets

Unix timestamp → datetime (stdlib)

import datetime # Seconds since epoch → UTC datetime ts = 1700000000 dt_utc = datetime.datetime.utcfromtimestamp(ts) print(dt_utc) # 2023-11-14 22:13:20 # With timezone awareness (recommended) dt_aware = datetime.datetime.fromtimestamp(ts, tz=datetime.timezone.utc) print(dt_aware.isoformat()) # 2023-11-14T22:13:20+00:00

datetime → Unix timestamp

import datetime dt = datetime.datetime(2024, 1, 15, 12, 0, 0, tzinfo=datetime.timezone.utc) unix_ts = int(dt.timestamp()) print(unix_ts) # 1705320000 # From string dt = datetime.datetime.strptime("2024-01-15 12:00:00", "%Y-%m-%d %H:%M:%S") dt = dt.replace(tzinfo=datetime.timezone.utc) print(int(dt.timestamp()))

Pandas: column of Unix timestamps → datetime

import pandas as pd df = pd.DataFrame({"ts": [1700000000, 1705320000, 1710000000]}) # Seconds df["datetime"] = pd.to_datetime(df["ts"], unit="s", utc=True) # Milliseconds df["datetime_ms"] = pd.to_datetime(df["ts_ms"], unit="ms", utc=True) # Convert to a specific timezone df["datetime_chile"] = df["datetime"].dt.tz_convert("America/Santiago") print(df.head())

Pandas: datetime column → Unix timestamp

import pandas as pd df = pd.DataFrame({"date": pd.to_datetime(["2024-01-15", "2024-03-01"])}) df["date"] = df["date"].dt.tz_localize("UTC") # make tz-aware first df["unix"] = df["date"].astype("int64") // 10**9 # nanoseconds → seconds print(df)

JavaScript Code Snippets

Unix → Date object

const ts = 1700000000; // JS uses milliseconds const date = new Date(ts * 1000); console.log(date.toISOString()); // "2023-11-14T22:13:20.000Z" console.log(date.toUTCString()); // "Tue, 14 Nov 2023 22:13:20 GMT" console.log(date.toLocaleString()); // locale-specific

Date → Unix timestamp

const date = new Date("2024-01-15T12:00:00Z"); const unixSeconds = Math.floor(date.getTime() / 1000); console.log(unixSeconds); // 1705320000 // Current timestamp const nowUnix = Math.floor(Date.now() / 1000);

SQL Snippets

PostgreSQL

-- Unix timestamp → timestamptz SELECT to_timestamp(1700000000); -- timestamptz → Unix SELECT EXTRACT(EPOCH FROM NOW())::BIGINT; -- Convert a column SELECT to_timestamp(created_at_unix) AT TIME ZONE 'America/Santiago' FROM events;

MySQL / MariaDB

-- Unix → datetime SELECT FROM_UNIXTIME(1700000000); -- datetime → Unix SELECT UNIX_TIMESTAMP(NOW());

What is a Unix timestamp?

A Unix timestamp (also called epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970 00:00:00 UTC — a reference point known as the Unix epoch. It is an integer, timezone-independent, and can represent any moment in time with a single number. Most systems store timestamps in seconds; JavaScript and some databases use milliseconds (multiply seconds by 1,000).

Common Unix timestamp reference values

Date (UTC)	Unix timestamp (seconds)
January 1, 1970 00:00:00	0
January 1, 2000 00:00:00	946684800
January 1, 2024 00:00:00	1704067200
January 1, 2025 00:00:00	1735689600
January 1, 2038 00:00:00	2145916800

Why use Unix timestamps?

Unix timestamps are the standard for time storage in software because they are timezone-independent— the same integer represents the same moment everywhere. They sort correctly as plain integers, compare with simple arithmetic, and fit in a single 32-bit or 64-bit integer column in a database. APIs, logs, and event systems use them to avoid ambiguity from daylight saving time, locale formats (MM/DD vs DD/MM), and timezone offsets.

Frequently asked questions

What is the difference between Unix time in seconds and milliseconds?

Most Unix timestamps count seconds since the epoch. JavaScript's Date.now() and many browser/Node.js APIs return milliseconds — 1,000× larger. A timestamp > 1e12 is almost certainly in milliseconds. Divide by 1000 to get seconds, or multiply seconds by 1000 to get milliseconds.

What happens at the Unix timestamp 2147483647?

On January 19, 2038 at 03:14:07 UTC, 32-bit signed integers overflow — this is the "Year 2038 problem". Systems using 32-bit Unix timestamps will wrap to a negative number. 64-bit timestamps (supported by modern systems) won't overflow for ~292 billion years.

How do I convert a Unix timestamp to a specific timezone?

Use datetime.fromtimestamp(ts, tz=pytz.timezone("America/New_York")) in Python, or new Date(ts * 1000).toLocaleString("en-US", { timeZone: "America/New_York" }) in JavaScript.