diff --git a/TODO.md b/TODO.md
index a502922..0f8fbf4 100644
--- a/TODO.md
+++ b/TODO.md
@@ -5,7 +5,7 @@ Remaining tasks sorted by priority for a working 1.0 release.
 ## P0: Critical for 1.0
 
 ### Image Processing
-- [ ] Add WebP encoding support (currently returns error)
+- [x] Add WebP encoding support (currently returns error)
 - [ ] Add AVIF encoding support (currently returns error)
 
 ### Manual Testing (verify auth/encrypted URLs work)
diff --git a/go.mod b/go.mod
index 6869ea4..4eec534 100644
--- a/go.mod
+++ b/go.mod
@@ -52,10 +52,12 @@ require (
 	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
+	github.com/ebitengine/purego v0.8.3 // indirect
 	github.com/emicklei/go-restful/v3 v3.12.1 // indirect
 	github.com/fatih/color v1.16.0 // indirect
 	github.com/felixge/httpsnoop v1.0.4 // indirect
 	github.com/fxamacker/cbor/v2 v2.9.0 // indirect
+	github.com/gen2brain/webp v0.5.5 // indirect
 	github.com/go-jose/go-jose/v4 v4.0.5 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
@@ -109,6 +111,7 @@ require (
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
 	github.com/ryanuber/go-glob v1.0.0 // indirect
 	github.com/spf13/pflag v1.0.10 // indirect
+	github.com/tetratelabs/wazero v1.9.0 // indirect
 	github.com/tidwall/gjson v1.18.0 // indirect
 	github.com/tidwall/match v1.1.1 // indirect
 	github.com/tidwall/pretty v1.2.0 // indirect
diff --git a/go.sum b/go.sum
index 9e7e92d..0e081d6 100644
--- a/go.sum
+++ b/go.sum
@@ -97,6 +97,8 @@ github.com/disintegration/imaging v1.6.2 h1:w1LecBlG2Lnp8B3jk5zSuNqd7b4DXhcjwek1
 github.com/disintegration/imaging v1.6.2/go.mod h1:44/5580QXChDfwIclfc/PCwrr44amcmDAg8hxG0Ewe4=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
+github.com/ebitengine/purego v0.8.3 h1:K+0AjQp63JEZTEMZiwsI9g0+hAMNohwUOtY0RPGexmc=
+github.com/ebitengine/purego v0.8.3/go.mod h1:iIjxzd6CiRiOG0UyXP+V1+jWqUXVjPKLAI0mRfJZTmQ=
 github.com/emicklei/go-restful/v3 v3.12.1 h1:PJMDIM/ak7btuL8Ex0iYET9hxM3CI2sjZtzpL63nKAU=
 github.com/emicklei/go-restful/v3 v3.12.1/go.mod h1:6n3XBCmQQb25CM2LCACGz8ukIrRry+4bhvbpWn3mrbc=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
@@ -110,6 +112,8 @@ github.com/fxamacker/cbor/v2 v2.7.0 h1:iM5WgngdRBanHcxugY4JySA0nk1wZorNOpTgCMedv
 github.com/fxamacker/cbor/v2 v2.7.0/go.mod h1:pxXPTn3joSm21Gbwsv0w9OSA2y1HFR9qXEeXQVeNoDQ=
 github.com/fxamacker/cbor/v2 v2.9.0 h1:NpKPmjDBgUfBms6tr6JZkTHtfFGcMKsw3eGcmD/sapM=
 github.com/fxamacker/cbor/v2 v2.9.0/go.mod h1:vM4b+DJCtHn+zz7h3FFp/hDAI9WNWCsZj23V5ytsSxQ=
+github.com/gen2brain/webp v0.5.5 h1:MvQR75yIPU/9nSqYT5h13k4URaJK3gf9tgz/ksRbyEg=
+github.com/gen2brain/webp v0.5.5/go.mod h1:xOSMzp4aROt2KFW++9qcK/RBTOVC2S9tJG66ip/9Oc0=
 github.com/getsentry/sentry-go v0.40.0 h1:VTJMN9zbTvqDqPwheRVLcp0qcUcM+8eFivvGocAaSbo=
 github.com/getsentry/sentry-go v0.40.0/go.mod h1:eRXCoh3uvmjQLY6qu63BjUZnaBu5L5WhMV1RwYO8W5s=
 github.com/go-chi/chi/v5 v5.2.3 h1:WQIt9uxdsAbgIYgid+BpYc+liqQZGMHRaUwp0JUcvdE=
@@ -379,6 +383,8 @@ github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+github.com/tetratelabs/wazero v1.9.0 h1:IcZ56OuxrtaEz8UYNRHBrUa9bYeX9oVY93KspZZBf/I=
+github.com/tetratelabs/wazero v1.9.0/go.mod h1:TSbcXCfFP0L2FGkRPxHphadXPjo1T6W+CseNNY7EkjM=
 github.com/tidwall/gjson v1.18.0 h1:FIDeeyB800efLX89e5a8Y0BNH+LOngJyGrIWxG2FKQY=
 github.com/tidwall/gjson v1.18.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
 github.com/tidwall/match v1.1.1 h1:+Ho715JplO36QYgwN9PGYNhgZvoUSc9X2c80KVTi+GA=
diff --git a/internal/imgcache/processor.go b/internal/imgcache/processor.go
index dc95f59..75f81f6 100644
--- a/internal/imgcache/processor.go
+++ b/internal/imgcache/processor.go
@@ -12,6 +12,7 @@ import (
 	"io"
 
 	"github.com/disintegration/imaging"
+	gowebp "github.com/gen2brain/webp"
 	"golang.org/x/image/webp"
 )
 
@@ -122,6 +123,7 @@ func (p *ImageProcessor) SupportedOutputFormats() []ImageFormat {
 		FormatJPEG,
 		FormatPNG,
 		FormatGIF,
+		FormatWebP,
 	}
 }
 
@@ -227,7 +229,14 @@ func (p *ImageProcessor) encode(img image.Image, format ImageFormat, quality int
 		}
 
 	case FormatWebP:
-		return nil, fmt.Errorf("%w: WebP encoding not supported", ErrUnsupportedOutputFormat)
+		options := gowebp.Options{
+			Lossless: false,
+			Quality:  quality,
+		}
+		err := gowebp.Encode(&buf, img, options)
+		if err != nil {
+			return nil, err
+		}
 
 	case FormatAVIF:
 		return nil, fmt.Errorf("%w: AVIF encoding not supported", ErrUnsupportedOutputFormat)
diff --git a/internal/templates/generator.html b/internal/templates/generator.html
index 84f9521..1621f7d 100644
--- a/internal/templates/generator.html
+++ b/internal/templates/generator.html
@@ -108,6 +108,7 @@
                         <option value="orig" {{if eq .FormFormat "orig"}}selected{{end}}>Original</option>
                         <option value="jpeg" {{if eq .FormFormat "jpeg"}}selected{{end}}>JPEG</option>
                         <option value="png" {{if eq .FormFormat "png"}}selected{{end}}>PNG</option>
+                        <option value="webp" {{if eq .FormFormat "webp"}}selected{{end}}>WebP</option>
                         <option value="gif" {{if eq .FormFormat "gif"}}selected{{end}}>GIF</option>
                     </select>
                 </div>