encoding/json.Unmarshal
standard libraryThe 5th most-called standard-library function by production calls. Called 199,655 times across 974 modules; 172,212 of those run outside tests and generated code.
0% in production calls vs 2026-W37 (171,857 → 172,212)
- prod calls
- 172,212
- non-test, non-generated
- all calls
- 199,655
- total callsites
- modules
- 974
- distinct callers
- in loop
- 51%
- of prod calls
- in tests
- 9%
- 18,571 calls
- resolved
- 100%
- to a known target
resolution mix
How each call resolves
How each call was attributed. Only resolved kinds, where the target function is known, count toward the ranking. Interface dispatch and unresolved receivers are reported separately and never guessed. Read the taxonomy →
- Package function100%A direct call to an exported package function, resolved by type.
estimate
Estimated relative cost
Roughly 31× the estimated relative cost of fmt.Sprintf . Benchmarked at 4403 ns/op × 172,212 production calls, normalized so fmt.Sprintf = 1.0.
This is not dollars and not a verdict. Per-op time depends heavily on inputs (argument sizes, contention, patterns), the benchmark ran on a single machine (darwin/arm64 (Apple Silicon), go1.26.0), and static call counts are not runtime frequency. How this is estimated →
who calls this
Notable callers
Production calls into Unmarshal from notable Go projects. Open one on the map to see what else it hammers.
- Kubernetes 648 <1%
- Docker 462 <1%
- Dgraph 324 <1%
- containerd 297 <1%
- Grafana 243 <1%
where it's called
Callsites in the wild
12 representative callsites of 199,655, prioritizing in-loop and non-test usage. We link to source, never display it.
- in loop
- in loop
-
charm.land/catwalk @v0.52.48
cmd/cortecs/main.go:119
in loop -
charm.land/fantasy @v0.44.0
providers/openaicompat/language_model_hooks.go:124
in loop - in loop
-
cockroachdb/cockroach @v19.2.12+incompatible
in loop - in loop
- in loop
- in loop
- in loop
-
moby/moby @v28.5.2+incompatible
in loop -
encr.dev @v1.58.6
cli/daemon/mcp/cache_tools.go:86
in loop
top callers
The modules that reach for it
The modules that call Unmarshal most in this snapshot.
- github.com/Azure/azure-sdk-for-go128,94665%
- github.com/labd/commercetools-go-sdk7,3684%
- github.com/jdcloud-api/jdcloud-sdk-go4,3112%
- github.com/okta/okta-sdk-golang/v53,2412%
- google.golang.org/api2,8361%
siblings
More from encoding/json
The other most-called functions in this package. See all →