ULID (Universally Unique Lexicographically Sortable Identifier) is a 26-character string format that combines a timestamp with random data to create identifiers that are both unique and sortable by creation time. ULIDs are an alternative to UUIDs with better sorting capabilities.

Why use ULIDs instead of UUIDs?

ULIDs offer several advantages over UUIDs: they are lexicographically sortable by generation time, they use a more compact representation (26 characters vs 36 for UUIDs), they're case-insensitive, and they avoid problematic characters like hyphens.

How do I convert a UUID to a ULID?

You can convert a UUID to a ULID using our UUID Converter tool. Simply paste your UUID into the input field and click Convert. The tool supports UUID v1, v4, v7, and any hex string, converting them losslessly to ULID format and back.

Can I decode a ULID to see its timestamp?

Yes, you can decode a ULID using our ULID Decoder tool. It will show you the timestamp in various formats (Unix timestamp, ISO string, human-readable date) and the random component in different representations.

Are ULIDs suitable for database primary keys?

Yes, ULIDs are excellent for database primary keys. They're sortable by creation time which improves database performance, they're URL-safe, and they can be generated without a central coordinator, making them ideal for distributed systems.

What is NanoID and when should I use it?

NanoID is a tiny, secure, URL-friendly unique string ID generator. It's smaller and faster than UUID and is ideal for generating short unique IDs for URLs, session tokens, or any situation where a compact random identifier is needed. Unlike ULID, NanoID is not time-sortable.

What is a Snowflake ID?

Snowflake ID is a 64-bit unique identifier format originally developed by Twitter. It encodes a timestamp, datacenter ID, machine ID, and sequence number. Snowflake IDs are sortable by time, extremely fast to generate, and widely used in distributed systems like Twitter, Discord, and Instagram.

How do I decode a JWT token?

Paste your JWT token into our JWT Decoder tool to instantly see the decoded header, payload, and signature. The tool shows all claims including expiry time (exp), issued-at (iat), and custom claims. No data is sent to any server — decoding is done entirely in your browser.

What is CUID and CUID2?

CUID (Collision-resistant Unique Identifier) is designed for horizontal scalability and sequential IDs for databases and distributed systems. CUID2 is the improved next generation with better security and randomness properties. Both are excellent alternatives to UUID for Node.js applications.

ULID Generator

Generate Universally Unique Lexicographically Sortable Identifiers with high performance

193,000,000

ULIDs Generated

1,500

ULIDs/Second

150

Active Users

Generate ULID Why ULID?

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NanoID Generator

Generate cryptographically secure NanoIDs with custom alphabet and length. NanoID is 40% smaller than UUID, URL-safe, and uses crypto.getRandomValues() for true randomness.

NanoID Generator -

Generate secure, collision-resistant, lightweight, URL-safe unique identifiers

Generator Settings

ID Length (Characters) 21

Quantity 1

Alphabet Presets

Custom Alphabet in Use

Birthday Collision Calculator

Calculate the probability of generating a duplicate NanoID based on your current alphabet size, selected length, and generation throughput.

Total Combinations 1.2 × 10³⁸

Collision Probability 1% Chance

Generation Speed (IDs/sec) 1,000 / sec

Time until 1% probability of collision:

41.6 million years

NanoID vs UUID vs ULID

Feature	NanoID	UUID v4	ULID
Default length	21 chars	36 chars	26 chars
Sortable by time	No	No	Yes
Custom alphabet	Yes	No	No
URL-safe	Yes	No (hyphens)	Yes
Cryptographically secure	Yes	Yes	Yes
Bundle size	~130 bytes	N/A	~620 bytes

When to use NanoID?

Short unique IDs for URLs and slugs
Session tokens and temporary keys
When you need a custom character set (e.g., numbers only)
Frontend-only ID generation without a backend

Related tools: ULID Generator UUID Converter Snowflake ID

Free Online Developer Tools – ULID, UUID, NanoID, CUID, Snowflake ID, JWT Decoder, Base64, JSON Formatter & More

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NanoID Generator

Birthday Collision Calculator

Generated NanoIDs

NanoID vs UUID vs ULID

When to use NanoID?

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