Timestamp Converter – Convert Timestamp Online (Free Tool)
Free online Timestamp Converter tool to convert Unix timestamps to human-readable dates and vice versa. Convert epoch time to datetime format, calculate time differences, and work with timestamps across timezones. Perfect for developers debugging logs and working with APIs.
What is Timestamp Converter?
Timestamp Converter switches a Unix epoch timestamp into a human-readable date and back. It supports seconds and milliseconds, local time and UTC, and the standard ISO 8601 format. Useful for debugging logs, building APIs that expose timestamps as numbers, or just converting a "1700000000" you saw in a database row into a real date.
Why use this tool?
- No API keys to manage and no rate limits to monitor
- 100% free with no hidden costs or daily limits
- Works offline after the first page load
- No telemetry on the tokens, payloads, or code you paste in
- Built for developer workflows: copy-friendly output, syntax-aware highlighting where useful
How to use
- Paste the input you want to process
- Adjust any optional flags or formatting settings
- Run the conversion — everything happens locally in your browser
- Copy the output for use in your project
Examples
Decode a log line
Paste 1700000000 to learn it is 2023-11-14T22:13:20Z — instantly readable for incident review.
Convert a JavaScript milliseconds timestamp
Date.now() returns milliseconds. Paste 1700000000000 and the tool detects the millisecond scale and converts to the matching date.
Build a future date
Pick a future date in the picker and get back the Unix timestamp to use as expires_at, valid_until, or a TTL value.
Common use cases
- Inspecting created_at / updated_at columns stored as integers
- Decoding JWT exp / iat / nbf claims
- Setting expires-at values for cache entries or signed URLs
- Working with Linux cron logs or system journals
- Building API responses that need both numeric and ISO representations
Troubleshooting
- Date came out 50+ years off.
- You probably mixed up seconds and milliseconds. Timestamps after year 2001 are about 1e9 in seconds and 1e12 in milliseconds — the tool auto-detects, but you can switch manually.
- Timezone seems wrong.
- The tool shows both UTC and your local zone. Pick the right one for the system you're debugging — servers usually log UTC, clients local.
- Negative timestamps confused.
- Negative epoch means before 1970-01-01. Most databases reject them; for historical dates, store as ISO strings instead.
Frequently Asked Questions
A Unix timestamp (also called epoch time) is the number of seconds that have elapsed since January 1, 1970 (UTC). It is a standard way to represent time in computing.
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