"fmt" imported and not used — how to fix

./main.go:4:2: "fmt" imported and not used

Quick fix: Delete the unused import line. Better: run goimports -w . (or enable format-on-save with gopls), which adds and removes imports for you. To keep a package for its side effects, import it as _ "pkg".

What it means

Every import must be used in that file. Unused imports slow down builds and hide mistakes, so the compiler rejects them.

Fix 1: remove it

import (
    "fmt"     // delete this if nothing in the file calls fmt.*
    "os"
)

Fix 2: let a tool handle imports

go install golang.org/x/tools/cmd/goimports@latest
goimports -w .

In VS Code with the Go extension (gopls), imports are organised on save by default.

Fix 3: imports for side effects

Some packages register themselves in init() (database drivers, image decoders, net/http/pprof). Import them with the blank identifier:

import (
    "database/sql"
    _ "github.com/lib/pq"
)

Fix 4: temporarily keep it while debugging

var _ = fmt.Println

Remove it when you're done.

Last updated 2026-10-27.