# UUID Version Generator (v1–v8) Generate RFC 9562 UUIDs — including the modern v6, v7 and v8 that most generators lack — or decode any UUID back to its version, variant and embedded timestamp. > Canonical page: https://elysiatools.com/en/tools/uuid-version-generator - **Category:** Development - **Keywords:** uuid generator, uuid v4 generator, uuid v7 generator, uuid v7 online, uuid v6, uuid v8, rfc 9562, guid generator, uuid decode ## Overview A full-range UUID generator covering every RFC 9562 version: v1 (time-based, Gregorian timestamp + node), v4 (random), v5 (deterministic SHA-1 namespaced with the DNS/URL/OID/X.500 namespaces), v6 (v1 with k-sortable reordered timestamp), v7 (48-bit Unix-millisecond timestamp + random — the database-friendly one that sorts correctly) and v8 (custom version field, filled with CSPRNG random here). Generate up to 100 at a time in lower- or uppercase. Switch to decode mode to parse any UUID: it reports the version, variant, and — for v1/v6/v7 — extracts the embedded timestamp and renders it as an exact UTC date, which is the quickest way to check whether a v7 is well-formed or where a v1 came from. The v5 mode is deterministic, so the same namespace + name always yields the same UUID. ## Inputs - **Mode** (select) - **Version** (select) - **How many** (number) - **Uppercase output** (checkbox) - **Namespace (v5)** (select) - **Name (v5 input)** (text): e.g. example.com - **UUID to decode** (text): e.g. 017f22e2-79b0-7cc3-98c4-dc0c0c07398f ## When to use - Creating sortable primary keys with UUIDv7 or UUIDv6 for database indexing and optimized write performance. - Generating deterministic UUIDv5 identifiers from specific namespaces (DNS, URL, OID, X.500) and names. - Decoding existing UUIDs to extract embedded timestamps, verify RFC 9562 compliance, or inspect version and variant metadata. ## How it works - Select your operating mode: choose 'Generate UUIDs' to create identifiers or 'Decode a UUID' to inspect an existing one. - If generating, select the desired UUID version (v1, v4, v5, v6, v7, or v8), configure options like count (up to 100), case format, or v5 namespace and name values. - If decoding, paste your UUID string to parse its components. - Receive instant output showing your generated UUID list or a full breakdown of the decoded UUID's version, variant, and human-readable UTC timestamp. ## Use cases - Provisioning batch UUIDv7 keys for high-throughput relational databases like PostgreSQL or MySQL. - Creating repeatable UUIDv5 resource identifiers from domain names or URLs for API entities. - Inspecting system audit logs by decoding UUID timestamps to trace the exact creation time of events. ## Frequently asked questions ### Why use UUIDv7 instead of UUIDv4 for database primary keys? UUIDv7 embeds a 48-bit millisecond Unix timestamp at the beginning, making values naturally time-ordered and significantly reducing B-tree index fragmentation compared to random UUIDv4. ### What is the difference between UUIDv1 and UUIDv6? Both use Gregorian timestamps and node IDs, but UUIDv6 reorders the timestamp bits to place the most significant time components first, enabling chronological sorting. ### Are UUIDv5 identifiers unique across repeated generations? UUIDv5 is deterministic: passing the same namespace and string name will always produce the identical UUID output. ### Which UUID versions support embedded timestamp extraction during decoding? Decode mode extracts and displays human-readable UTC timestamps for time-based versions: v1, v6, and v7. ### How many UUIDs can I generate in a single request? You can generate anywhere from 1 to 100 UUIDs per run in either lowercase or uppercase formatting. ## Related tools - [Modern Unique ID Generator](https://elysiatools.com/en/tools/uid-generator): Generate modern unique identifiers: ULID, NanoID, Snowflake and CUID2. Compare formats, decode ULID timestamps and pick the right ID for your system. - [ULID / NanoID / KSUID / Snowflake ID Decoder](https://elysiatools.com/en/tools/ulid-nanoid-ksuid-snowflake-id-decoder): Decode lexically sortable IDs losslessly with BigInt: ULID (Crockford base32), KSUID (base62), NanoID, MongoDB ObjectId, and Discord/Twitter/Sonyflake Snowflakes — with ISO timestamps, raw hex, bit-level field breakdowns and birthday-bound collision probabilities. - [JavaScript Deobfuscator](https://elysiatools.com/en/tools/javascript-deobfuscator): Deobfuscate and analyze obfuscated JavaScript code to improve readability and understanding - [NTP RFC 5905 / SNTP Leap Second & Epoch Decoder](https://elysiatools.com/en/tools/ntp-rfc-5905-sntp-leap-second-epoch-decoder): Decode an NTP/SNTP 48-byte packet: LI/VN/Mode bitfield, stratum, poll, precision, root delay/dispersion, reference ID (with clock & kiss codes), and four 64-bit 1900-epoch timestamps - [Snowflake / Discord ID Bit Decoder](https://elysiatools.com/en/tools/snowflake-discord-id-bit-decoder): Decode 64-bit Snowflake-style IDs for Discord, Twitter, Mastodon, Sonyflake, Instagram, or a custom bit profile. Extract timestamp, worker/process/machine, sequence fields, align platform epochs, and infer a Discord shard when a shard count is supplied. - [ASCII85 Converter](https://elysiatools.com/en/tools/ascii85-converter): Encode and decode text to/from ASCII85 format (Adobe version) - [Audio Read-Along Cue Generator](https://elysiatools.com/en/tools/audio-read-along-cue-generator): Generate sentence or word-level timestamp cues from a narration audio and its script, for karaoke-style reading and language learning. - [Base45 Converter](https://elysiatools.com/en/tools/base45-converter): Encode and decode text to/from Base45 format (RFC 9285) ## Samples - [Web Image Processing Python Samples](https://elysiatools.com/en/samples/web-image-processing-python): Web Python image processing examples using PIL/Pillow including reading, saving, resizing, and format conversion - [Android Image Processing Java Samples](https://elysiatools.com/en/samples/android-image-processing-java): Android Java image processing examples including reading/saving images, scaling, and format conversion - [Android Image Processing Kotlin Samples](https://elysiatools.com/en/samples/android-image-processing-kotlin): Android Kotlin image processing examples including reading/saving images, scaling, and format conversion - [Web Image Processing Rust Samples](https://elysiatools.com/en/samples/web-image-processing-rust): Web Rust image processing examples including image read/save, scaling, and format conversion