UUID v7 Generator
Generate sortable UUID v7 IDs
Choose the count and output format first to generate UUID v7 values; dedupe demos and extra notes are available in Advanced mode.
The full guide also includes pitfalls, worked examples, snippets, FAQs, and related tools for checking results or troubleshooting.
About this tool
Generate UUID v7 values with 48 timestamp bits, version and variant fields, and 74 browser-crypto random bits. This tool supports integer Unix milliseconds from 0 to 281474976710655 without timestamp wrapping. Generate 1–50 values; uppercase and compact options reformat the same IDs. Optional dedupe hides duplicate values without generating replacements. Ordering is not monotonic within a millisecond or across clock rollback, and uniqueness is not guaranteed. Generated IDs are not authentication secrets.
Production Snippets
Example
text
018bcfe5-6800-7fff-bfff-ffffffffffff
Encoded time: 2023-11-14T22:13:20.000ZSuggested Workflow
Coordinate Release Times with UTC and Check the DST Boundary
Reproduce January and July 2026 conversions for New York, Shanghai, and London, then distinguish the two New York 01:30 times at the end of daylight saving time.
Choose an ID Format and Verify Its Encoding Contract
Compare UUID v7 and NanoID use cases, reproduce A → QQ== or A → 28, and distinguish byte encoding from numeric ID conversion and authentication.
Failure Clinic (Common Pitfalls)
Dedupe is only a view of one batch
Cause: Repeated values are hidden without replacement, and no other batches or systems are consulted.
Fix: Enforce application uniqueness at the data store and do not treat this option as global coordination.
Scenario Recipes
Prepare a v7 fixture and change its representation
Goal: Keep identifiers stable while comparing text formats.
- Generate two UUID v7 values and note their ISO timestamps.
- Toggle uppercase and Remove hyphens.
- Confirm only representation changed; generate again only when new IDs are needed.
Result: Compact output contains the same bits, but some downstream validators require the canonical hyphenated form.
Frequently Asked Questions
What does this UUID v7 generator encode?
It uses the RFC 9562 UUID v7 field layout: 48-bit Unix milliseconds, version 7, RFC variant and 74 random bits. This UI rejects clocks outside 0–281474976710655 ms rather than wrapping their timestamps.
Can I request fractional or unlimited counts?
No. Count must be an integer from 1 to 50. Invalid values show an error and do not produce a partial batch.
Do formatting and dedupe options make new IDs?
No. Uppercase and compact options reformat existing values. Dedupe hides repeated values in the current batch without replacements; turning it off restores the full batch.
Are IDs strictly ordered or guaranteed unique?
No. The timestamp prefix supports time grouping, but same-millisecond randomness and clock rollback can change order. Collisions remain possible.
Can I use the output as an API key?
Use it as an identifier, not an authentication secret. Browser crypto failures stop generation and show an error; no weak random fallback is used.
Are IDs uploaded or persisted?
Generation is local. Count and output options are stored in this browser; generated IDs are not persisted by the tool. Clear removes its settings draft.
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