How many ticks are in a second?

Exactly 10,000,000 ticks — each tick is 100 nanoseconds.

What is the difference between .NET ticks and Windows FILETIME?

Both use 100-nanosecond units, but .NET ticks count from 0001-01-01 while FILETIME counts from 1601-01-01. They differ by a fixed offset of 504,911,232,000,000,000 ticks.

How do I get Unix time from a C# DateTime?

Use new DateTimeOffset(dateTime.ToUniversalTime()).ToUnixTimeSeconds() or .ToUnixTimeMilliseconds().

.NET Ticks Converter

.NET Ticks to Unix Timestamp Converter

Convert a .NET DateTime.Ticks value to a Unix timestamp in seconds and milliseconds, ISO 8601, and a readable date. .NET ticks count 100-nanosecond intervals since January 1, 0001.

.NET DateTime.Ticks

100-ns intervals since 0001-01-01

Timezone

Current time — .NET DateTime.Ticks—

Unix timestamp (s)—

Open Converter Timestamp Formats

What are .NET ticks?

In .NET, DateTime.Ticks and TimeSpan.Ticks measure time in 100-nanosecond units. A DateTime tick count is the number of 100-nanosecond intervals since 00:00:00 on January 1, 0001 in the proleptic Gregorian calendar.

Epoch: 0001-01-01 00:00:00
Resolution: 100-nanosecond ticks (10,000,000 per second)
A present-day value is around 6.4 × 10^17
C#: DateTime.UtcNow.Ticks, DateTimeOffset.UtcNow.Ticks

How to convert .NET ticks to a Unix timestamp

There are 62,135,596,800 seconds between 0001-01-01 and 1970-01-01. Divide ticks by 10,000,000 for seconds since year 1, then subtract that offset.

Unix seconds = Ticks / 10000000 − 62135596800
Unix milliseconds = Ticks / 10000 − 62135596800000
Example: 638355968000000000 → 1700000000 → 2023-11-14 22:13:20 UTC
In C#: new DateTimeOffset(dt).ToUnixTimeSeconds() does this for you

C# code and edge cases

Modern .NET offers DateTimeOffset.ToUnixTimeSeconds() and ToUnixTimeMilliseconds(), and DateTimeOffset.FromUnixTimeSeconds() for the reverse. Use ticks directly only when interoperating with serialized data. Note that DateTime.Ticks ignores the DateTimeKind, so always normalize to UTC first.

C#: var unixSeconds = new DateTimeOffset(dt.ToUniversalTime()).ToUnixTimeSeconds();
C#: var dt = DateTimeOffset.FromUnixTimeMilliseconds(ms).UtcDateTime;
Ticks of 0 = 0001-01-01; DateTime.MaxValue.Ticks = 3155378975999999999
Values exceed JavaScript safe integers, so this converter uses BigInt

Related timestamp format converters

Library and serialization notes

Ticks turn up in older .NET serialization formats and JSON conventions. Watch for:

Legacy Microsoft JSON dates: "/Date(1700000000000+0000)/" wrap milliseconds (not ticks)
DateTimeOffset.UnixEpoch is the standard zero point in modern .NET
DateTime.MaxValue.Ticks = 3155378975999999999; values that high almost certainly indicate a "never" sentinel
TimeSpan.Ticks is the same unit but measured as a duration; do not subtract a DateTime tick from a TimeSpan tick blindly
Newtonsoft.Json and System.Text.Json both default to ISO 8601 — prefer that over raw ticks where you have the choice

FAQ

How many ticks are in a second?: Exactly 10,000,000 ticks — each tick is 100 nanoseconds.
What is the difference between .NET ticks and Windows FILETIME?: Both use 100-nanosecond units, but .NET ticks count from 0001-01-01 while FILETIME counts from 1601-01-01. They differ by a fixed offset of 504,911,232,000,000,000 ticks.
How do I get Unix time from a C# DateTime?: Use new DateTimeOffset(dateTime.ToUniversalTime()).ToUnixTimeSeconds() or .ToUnixTimeMilliseconds().