Fast cryptographically secure Guid generator for Go.
By Stan Drapkin.
Guid
is defined as type Guid [16]byte
and filled with 128 cryptographically strong bits.
package main
import (
"fmt"
"github.com/sdrapkin/guid"
)
func main() {
for range 4 {
fmt.Printf("%x\n", guid.New())
}
fmt.Println()
for range 4 {
g := guid.New()
fmt.Println(&g) // calls g.String()
}
}
79c9779af20dcd21fbe60f3b336ed08c
da2026d38edca4371a476efd41333d23
88c3033b002b0e73321509ef26de607f
a84e961ff7f09f5210ea04585f152e73
WF8MvK5CUOrI-enEuvS0jw
AOp8Voi5knpu1mg3RjzmSg
gxOQRIVR4B_uGHD6OP76XA
Zo_hpnDxkOsAWLk1tIS6DA
guid
is a high-performance, cryptographically secure UUID/GUID (Globally Unique Identifier) generator for Go. It's built for speed without compromising on security, offering a significant performance advantageβup to 10x faster than github.com/google/uuid
.
Beyond raw speed, guid
offers:
- Cryptographically Strong: Generates 128 cryptographically secure bits for robust, unique identifiers.
- Optimized for Databases: Includes special
GuidPG
andGuidSS
types that generate sequential Guids, dramatically improvingINSERT
performance and preventing index fragmentation in PostgreSQL and SQL Server databases. - Seamless Interoperability: Easily integrate with existing
google/uuid
codebases, and even boostuuid
's performance by up to 4x usingguid.Reader
. - FIPS 140 Compliant: Ensures adherence to stringent security standards.
- Zero Allocations for Core Operations:
guid.New()
generates new Guids with no memory allocations, making it incredibly efficient.
guid.New()
is 6~10 nsguid.NewString()
is 40~60 nsString()
on existing guid is ~40 ns- multi-goroutine calls do not increase per-call latency
- if your library is faster - please let me know!
All APIs are safe for concurrent use by multiple goroutines.
Functions | Description |
---|---|
guid.New() Guid |
Generate a new Guid |
guid.NewString() string |
Generate a new Guid as a Base64Url string |
guid.NewPG() GuidPG |
Generate a new PostgreSQL sequential Guid |
guid.NewSS() GuidSS |
Generate a new SQL Server sequential Guid |
guid.Parse(s string) (Guid, error) |
Parse a Base64Url string into a Guid |
guid.ParseBytes(src []byte) (Guid, error) |
Parse Base64Url bytes to a Guid |
guid.FromBytes(src []byte) (Guid, error) |
Parse 16-byte slice to a Guid |
guid.DecodeBase64URL(dst []byte, src []byte) (ok bool) |
Decode a Base64Url slice into a Guid slice |
guid.Reader π₯ implements io.Reader |
Faster alternative to crypto/rand |
guid.Nil | The zero-value Guid |
Guid methods |
Description |
---|---|
.String() string |
Encodes the Guid into Base64Url 22-char string fmt.Stringer |
.EncodeBase64URL(dst []byte) error |
Like .String() but encodes into len(22) byte slice |
.MarshalBinary() | Implements encoding.BinaryMarshaler |
.UnmarshalBinary() | Implements encoding.BinaryUnmarshaler |
.MarshalText() | Implements encoding.TextMarshaler |
.UnmarshalText() | Implements encoding.TextUnmarshaler |
GuidPG , GuidSS methods |
Description |
---|---|
.Timestamp() time.Time |
Extracts the UTC timestamp |
guid
includes two special types GuidPG
and GuidSS
optimized for use as database primary keys (PostgreSQL and SQL Server). Their time-ordered composition helps prevent index fragmentation and improves INSERT
performance compared to fully random Guids. Note that sequential sorting is only across time.Now()
timestamp precision.
guid.NewPG()
: Generates aGuidPG
, which is sortable in PostgreSQL.- It is structured as
[8-byte timestamp][8 random bytes]
.
- It is structured as
guid.NewSS()
: Generates aGuidSS
, which is sortable in SQL Server.- It is structured as
[8 random bytes][8-byte SQL Server-ordered timestamp]
.
- It is structured as
.Timestamp()
onGuidPG
/GuidSS
returns Guid creation time as UTCtime.Time
.
Both GuidPG
and GuidSS
are nearly as fast as guid.New()
. They can be used as a standard Guid
and support the same interfaces.
fmt.Printf("%s\t %s\t\t\t\t%s\t %s\n",
"gpg.String()", "hex(gpg)", "gss.String()", "hex(gss)")
for range 10 {
gpg := guid.NewPG()
gss := guid.NewSS()
fmt.Println(&gpg, hex.EncodeToString(gpg.Guid[:]), &gss, hex.EncodeToString(gss.Guid[:]))
}
gpg := guid.NewPG()
gss := guid.NewSS()
fmt.Println(gpg.Timestamp()) // time.Time
fmt.Println(gss.Timestamp()) // time.Time
gpg.String() hex(gpg) gss.String() hex(gss)
GFEU88wgQvDlahOowSGTKA 185114f3cc2042f0e56a13a8c1219328 9SurLKL6ti2l0BhRFPPMKA f52bab2ca2fab62da5d0185114f3cc28
GFEU88wopdChlFba89-4yg 185114f3cc28a5d0a19456daf3dfb8ca yTRE6Rr1gISl0BhRFPPMKA c93444e91af58084a5d0185114f3cc28
GFEU88ww9fA01GntVDQ_4w 185114f3cc30f5f034d469ed54343fe3 8SaILyee6q718BhRFPPMMA f126882f279eeaaef5f0185114f3cc30
GFEU88ww9fASNFzZQJpv7Q 185114f3cc30f5f012345cd9409a6fed xZ3KYLzqJ0f18BhRFPPMMA c59dca60bcea2747f5f0185114f3cc30
GFEU88ww9fAHgWvjAmkQJw 185114f3cc30f5f007816be302691027 yEif2kTQBcD18BhRFPPMMA c8489fda44d005c0f5f0185114f3cc30
GFEU88ww9fD4_Vm3PG5Vuw 185114f3cc30f5f0f8fd59b73c6e55bb SRKgSiCc-gL18BhRFPPMMA 4912a04a209cfa02f5f0185114f3cc30
GFEU88ww9fDzO_One7T6BA 185114f3cc30f5f0f33bf3a77bb4fa04 rGr2czgQcmr18BhRFPPMMA ac6af6733810726af5f0185114f3cc30
GFEU88w5PqQAifEi5tqoWQ 185114f3cc393ea40089f122e6daa859 5YYbiI3p7P4-pBhRFPPMOQ e5861b888de9ecfe3ea4185114f3cc39
GFEU88w5PqSFkX4bmxSvMQ 185114f3cc393ea485917e1b9b14af31 PqUPeiyessU-pBhRFPPMOQ 3ea50f7a2c9eb2c53ea4185114f3cc39
GFEU88w5PqTsYX0kcZzL6Q 185114f3cc393ea4ec617d24719ccbe9 yFIlRwKZJNo-pBhRFPPMOQ c8522547029924da3ea4185114f3cc39
2025-07-11 03:32:47.3597457 +0000 UTC
2025-07-11 03:32:47.3597457 +0000 UTC
- If you must keep using
google/uuid
, useguid
to increase performance by 2~4x:
// do this before using google/uuid
uuid.SetRand(guid.Reader)
- Quick conversions between
guid
andgoogle/uuid
if you needuuid
behavior:
g := guid.New()
gpg := guid.NewPG()
gss := guid.NewSS()
var u uuid.UUID
u = uuid.UUID(g) // copy by value
fmt.Println(u)
u = uuid.UUID(gpg.Guid) // copy by value
fmt.Println(u)
u = uuid.UUID(gss.Guid) // copy by value
fmt.Println(u)
uptr := (*uuid.UUID)(unsafe.Pointer(&g)) // zero-copy cast
g[0], g[1] = 0xAB, 0xCD
fmt.Println(uptr)
05166521-a124-9d0c-cb11-7f0cbf3a030c
1852e32a-5aac-bb9c-bffc-b330606813af
7e8badae-57f8-c88d-bb9c-1852e32a5aac
abcd6521-a124-9d0c-cb11-7f0cbf3a030c
- FIPS-140 ready (https://go.dev/doc/security/fips140)
- set
GODEBUG=fips140=on
environment variable - https://go.dev/blog/fips140
- set
Benchmark Name | Time per Op | Bytes per Op | Allocs per Op |
---|---|---|---|
Benchmark_uuid_New_x10-8 | 3031 ns/op | 160 B/op | 10 allocs/op |
Benchmark_uuid_New_guidRand_x10-8 π₯ | 862.0 ns/op | 160 B/op | 10 allocs/op |
Benchmark_uuid_New_RandPool_x10-8 | 747.6 ns/op | 0 B/op | 0 allocs/op |
Benchmark_uuid_New_RandPool_guidRand_x10-8 π₯ | 516.8 ns/op | 0 B/op | 0 allocs/op |
Benchmark_uuid_New_Parallel_x10-8 | 1230 ns/op | 160 B/op | 10 allocs/op |
Benchmark_uuid_New_Parallel_guidRand_x10-8 π₯ | 510.0 ns/op | 160 B/op | 10 allocs/op |
Benchmark_uuid_New_Parallel_RandPool_x10-8 | 1430 ns/op | 0 B/op | 0 allocs/op |
Benchmark_uuid_New_Parallel_RandPool_guidRand_x10-8 π₯ | 1185 ns/op | 0 B/op | 0 allocs/op |
Guid Benchmarks [raw]
go test -bench=.* -benchtime=4s
goos: windows
goarch: amd64
pkg: github.com/sdrapkin/guid
cpu: Intel(R) Core(TM) i7-10510U CPU @ 1.80GHz
Benchmarks guid [10 calls] | Time/op | Bytes/op | Allocs/op |
---|---|---|---|
guid_New_x10-8 | 203.4 ns/op | 0 B/op | 0 allocs/op |
guid_NewString_x10-8 | 582.4 ns/op | 240 B/op | 10 allocs/op |
guid_String_x10-8 | 388.9 ns/op | 240 B/op | 10 allocs/op |
guid_New_Parallel_x10-8 π₯ | 62.45 ns/op | 0 B/op | 0 allocs/op |
guid_NewString_Parallel_x10-8 | 374.2 ns/op | 240 B/op | 10 allocs/op |
guid.NewPG() vs uuid.NewV7() [10 calls] |
Time/op | |
---|---|---|
guid.NewPG()_x10_Sequential | 386.4 ns/op | |
uuid.NewV7()_x10_Sequential | 887.9 ns/op | 2.3x slower β³ |
guid.NewPG()_x10_Parallel | 144.3 ns/op | |
uuid.NewV7()_x10_Parallel | 2575 ns/op | 18x slower β³ |
Benchmarks nanoid v1.35 [10 calls] | Time/op | Bytes/op | Allocs/op |
---|---|---|---|
guid.NewString() x10 Sequential |
609.9 ns/op | 240 B/op | 10 allocs/op |
guid.NewString() x10 Parallel (8 CPU) |
384.0 ns/op | 240 B/op | 10 allocs/op |
nanoid.New() x10 Sequential |
2257 ns/op | 240 B/op | 10 allocs/op |
nanoid.New() x10 Parallel (8 CPU) |
1337 ns/op | 240 B/op | 10 allocs/op |
Benchmarks uuid [10 calls] | Time/op | Bytes/op | Allocs/op |
---|---|---|---|
uuid_New_x10-8 | 2216 ns/op | 160 B/op | 10 allocs/op |
uuid_New_RandPool_x10-8 | 528.2 ns/op | 0 B/op | 0 allocs/op |
uuid_New_Parallel_x10-8 | 1064 ns/op | 160 B/op | 10 allocs/op |
uuid_New_RandPool_Parallel_x10-8 | 1301 ns/op | 0 B/op | 0 allocs/op |
Benchmarks [20 guid encodings] | Time/op | Bytes/op | Allocs/op |
---|---|---|---|
g.String-8 | 1025 ns/op | 480 B/op | 20 allocs/op |
base64.RawURLEncoding.EncodeToString-8 | 1867 ns/op | 960 B/op | 40 allocs/op |
g.EncodeBase64URL-8 | 392.0 ns/op | 0 B/op | 0 allocs/op |
base64.RawURLEncoding.Encode-8 | 463.4 ns/op | 0 B/op | 0 allocs/op |
Full go doc
style documentation: https://pkg.go.dev/github.com/sdrapkin/guid
- Go 1.24+
To install the guid
package, run the following command:
go get -u github.com/sdrapkin/guid
To use the guid
package in your Go project, import it as follows:
import "github.com/sdrapkin/guid"
Guid
supports JSON marshalling and unmarshalling for both value and pointer types:
- Value fields serialize as 22-character Base64Url strings.
- Pointer fields serialize as strings or
null
(for nil pointers). - Zero-value Guids (
guid.Nil
) are handled correctly.
type User struct {
ID guid.Guid `json:"id"`
ManagerID *guid.Guid `json:"mid"`
}
u, u2 := User{ID: guid.New()}, User{}
data, _ := json.Marshal(u)
fmt.Println(string(data)) // {"id":"tI0EMdDXpOcvvGLktob4Ug","mid":null}
_ = json.Unmarshal(data, &u2)
fmt.Println(u2.ID == u.ID) // true