diff --git a/main.go b/main.go
index 2f0fcdc..56b2b08 100644
--- a/main.go
+++ b/main.go
@@ -17,16 +17,18 @@ import (
 )
 
 var (
-	app    *qt.QApplication
-	window *qt.QMainWindow
+	app       *qt.QApplication
+	window    *qt.QMainWindow
+	tabWidget *qt.QTabWidget
 
 	currentSec   nostr.SecretKey
 	currentKeyer nostr.Keyer
 	statusLabel  *qt.QLabel
-	debounced    = debouncer.New(800 * time.Millisecond)
+	debounced    = debouncer.New(950 * time.Millisecond)
 	sys          = sdk.NewSystem()
 	ctx          = context.Background()
 	debug        = flag.Bool("debug", false, "enable debug mode")
+	initialTab   = flag.String("tab", "paste", "tab to open initially")
 )
 
 func main() {
@@ -130,13 +132,26 @@ func main() {
 		keyChanged(nsec)
 	})
 
-	tabWidget := qt.NewQTabWidget(centralWidget)
+	tabWidget = qt.NewQTabWidget(centralWidget)
 
 	eventTab := setupEventTab()
 	reqTab := setupReqTab()
+	pasteTab := setupPasteTab()
 
 	tabWidget.AddTab(eventTab, "event")
 	tabWidget.AddTab(reqTab, "req")
+	tabWidget.AddTab(pasteTab, "paste")
+
+	switch *initialTab {
+	case "event":
+		tabWidget.SetCurrentIndex(0)
+	case "req":
+		tabWidget.SetCurrentIndex(1)
+	case "paste":
+		tabWidget.SetCurrentIndex(2)
+	default:
+		tabWidget.SetCurrentIndex(2)
+	}
 
 	mainLayout.AddWidget(tabWidget.QWidget)
 
@@ -146,6 +161,7 @@ func main() {
 	// initial render
 	updateEvent()
 	updateReq()
+	updatePaste()
 
 	window.Show()
 	qt.QApplication_Exec()
diff --git a/paste.go b/paste.go
new file mode 100644
index 0000000..4947bc5
--- /dev/null
+++ b/paste.go
@@ -0,0 +1,405 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"fiatjaf.com/nostr"
+	"fiatjaf.com/nostr/nip05"
+	"fiatjaf.com/nostr/nip19"
+	"github.com/btcsuite/btcd/btcec/v2"
+	qt "github.com/mappu/miqt/qt6"
+	"github.com/mappu/miqt/qt6/mainthread"
+)
+
+type pasteVars struct {
+	inputEdit  *qt.QTextEdit
+	outputVBox *qt.QVBoxLayout
+
+	nip05ctxCancel context.CancelFunc
+	nip05ctxAbort  error
+}
+
+var paste = pasteVars{
+	nip05ctxAbort: errors.New("aborted"),
+}
+
+func setupPasteTab() *qt.QWidget {
+	tab := qt.NewQWidget(window.QWidget)
+	layout := qt.NewQVBoxLayout2()
+	tab.SetLayout(layout.QLayout)
+
+	// input
+	inputLabel := qt.NewQLabel2()
+	inputLabel.SetText("paste:")
+	layout.AddWidget(inputLabel.QWidget)
+	paste.inputEdit = qt.NewQTextEdit(tab)
+	layout.AddWidget(paste.inputEdit.QWidget)
+	paste.inputEdit.OnTextChanged(updatePaste)
+
+	// output
+	paste.outputVBox = qt.NewQVBoxLayout2()
+	layout.AddLayout(paste.outputVBox.QLayout)
+
+	return tab
+}
+
+func deleteLayoutRecursively(layout *qt.QLayout) {
+	for layout.Count() > 0 {
+		layoutItem := layout.ItemAt(0)
+		if w := layoutItem.Widget(); w != nil {
+			w.DeleteLater()
+		} else if subLayout := layoutItem.Layout(); subLayout != nil {
+			deleteLayoutRecursively(subLayout)
+		}
+		layout.RemoveItem(layoutItem)
+	}
+	layout.DeleteLater()
+}
+
+func updatePaste() {
+	// clear previous output
+	for paste.outputVBox.Count() > 0 {
+		item := paste.outputVBox.ItemAt(0)
+		if widget := item.Widget(); widget != nil {
+			widget.DeleteLater()
+		} else if layout := item.Layout(); layout != nil {
+			deleteLayoutRecursively(layout)
+		}
+		paste.outputVBox.RemoveItem(item)
+	}
+
+	text := strings.TrimSpace(paste.inputEdit.ToPlainText())
+	if text == "" {
+		return
+	}
+
+	// try nip19 decode
+	if prefix, decoded, err := nip19.Decode(text); err == nil {
+		paste.displayNip19Decoded(prefix, decoded)
+		return
+	}
+
+	// try nip05
+	if nip05.IsValidIdentifier(text) {
+		debounced.Call(func() {
+			if nip05.IsValidIdentifier(text) {
+				paste.displayNip05(text)
+			}
+		})
+		return
+	}
+
+	// try JSON event
+	var event nostr.Event
+	if err := json.Unmarshal([]byte(text), &event); err == nil {
+		paste.displayEventButton(event)
+		return
+	}
+
+	// try JSON filter
+	var filter nostr.Filter
+	if err := json.Unmarshal([]byte(text), &filter); err == nil {
+		paste.displayFilterButton(filter)
+		return
+	}
+
+	// if nothing worked, show error
+	errorLabel := qt.NewQLabel2()
+	errorLabel.SetText("could not decode input")
+	paste.outputVBox.AddWidget(errorLabel.QWidget)
+}
+
+func (p *pasteVars) displayNip19Decoded(prefix string, decoded interface{}) {
+	switch prefix {
+	case "nsec":
+		if sk, ok := decoded.(nostr.SecretKey); ok {
+			p.displayNsec(sk)
+		}
+	case "npub":
+		if pk, ok := decoded.(nostr.PubKey); ok {
+			p.displayPubKey(pk)
+		}
+	case "note":
+		if id, ok := decoded.(nostr.ID); ok {
+			p.displayEventID(id)
+		}
+	case "nevent":
+		if ep, ok := decoded.(nostr.EventPointer); ok {
+			p.displayEventPointer(ep)
+			p.displayPointerTag(ep)
+		}
+	case "nprofile":
+		if pp, ok := decoded.(nostr.ProfilePointer); ok {
+			p.displayProfilePointer(pp)
+			p.displayPointerTag(pp)
+		}
+	case "naddr":
+		if ap, ok := decoded.(nostr.EntityPointer); ok {
+			p.displayAddressPointer(ap)
+			p.displayPointerTag(ap)
+		}
+	default:
+		label := qt.NewQLabel2()
+		label.SetText(fmt.Sprintf("decoded %s: %v", prefix, decoded))
+		p.outputVBox.AddWidget(label.QWidget)
+	}
+}
+
+func (p *pasteVars) displayNsec(sk nostr.SecretKey) {
+	// nsec
+	nsecLabel := qt.NewQLabel2()
+	nsecLabel.SetText("nsec:")
+	p.outputVBox.AddWidget(nsecLabel.QWidget)
+	nsec := nip19.EncodeNsec(sk)
+	nsecEdit := qt.NewQLineEdit(window.QWidget)
+	nsecEdit.SetText(nsec)
+	nsecEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(nsecEdit.QWidget)
+
+	// hex
+	hexLabel := qt.NewQLabel2()
+	hexLabel.SetText("hex:")
+	p.outputVBox.AddWidget(hexLabel.QWidget)
+	hexEdit := qt.NewQLineEdit(window.QWidget)
+	hexEdit.SetText(sk.Hex())
+	hexEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(hexEdit.QWidget)
+
+	// npub
+	npubLabel := qt.NewQLabel2()
+	npubLabel.SetText("corresponding npub:")
+	p.outputVBox.AddWidget(npubLabel.QWidget)
+	_, pub := btcec.PrivKeyFromBytes(sk[:])
+	pk := nostr.PubKey(pub.SerializeCompressed()[1:])
+	npub := nip19.EncodeNpub(pk)
+	npubEdit := qt.NewQLineEdit(window.QWidget)
+	npubEdit.SetText(npub)
+	npubEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(npubEdit.QWidget)
+}
+
+func (p *pasteVars) displayPubKey(pk nostr.PubKey) {
+	npubLabel := qt.NewQLabel2()
+	npubLabel.SetText("npub:")
+	p.outputVBox.AddWidget(npubLabel.QWidget)
+	npub := nip19.EncodeNpub(pk)
+	npubEdit := qt.NewQLineEdit(window.QWidget)
+	npubEdit.SetText(npub)
+	npubEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(npubEdit.QWidget)
+
+	hexLabel := qt.NewQLabel2()
+	hexLabel.SetText("hex:")
+	p.outputVBox.AddWidget(hexLabel.QWidget)
+	hexEdit := qt.NewQLineEdit(window.QWidget)
+	hexEdit.SetText(pk.Hex())
+	hexEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(hexEdit.QWidget)
+}
+
+func (p *pasteVars) displayEventID(id nostr.ID) {
+	hexLabel := qt.NewQLabel2()
+	hexLabel.SetText("id (hex):")
+	p.outputVBox.AddWidget(hexLabel.QWidget)
+	hexEdit := qt.NewQLineEdit(window.QWidget)
+	hexEdit.SetText(id.Hex())
+	hexEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(hexEdit.QWidget)
+}
+
+func (p *pasteVars) displayPointerTag(pointer nostr.Pointer) {
+	tagLabel := qt.NewQLabel2()
+	tagLabel.SetText("tag reference:")
+	p.outputVBox.AddWidget(tagLabel.QWidget)
+	tagEdit := qt.NewQLineEdit(window.QWidget)
+	tagj, _ := json.Marshal(pointer.AsTag())
+	tagEdit.SetText(string(tagj))
+	tagEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(tagEdit.QWidget)
+}
+
+func (p *pasteVars) displayEventPointer(ep nostr.EventPointer) {
+	p.displayEventID(ep.ID)
+	if ep.Author != nostr.ZeroPK {
+		authorLabel := qt.NewQLabel2()
+		authorLabel.SetText("author:")
+		p.outputVBox.AddWidget(authorLabel.QWidget)
+		authorEdit := qt.NewQLineEdit(window.QWidget)
+		authorEdit.SetText(ep.Author.Hex())
+		authorEdit.SetReadOnly(true)
+		p.outputVBox.AddWidget(authorEdit.QWidget)
+	}
+	p.displayRelays(ep.Relays)
+}
+
+func (p *pasteVars) displayProfilePointer(pp nostr.ProfilePointer) {
+	p.displayPubKey(pp.PublicKey)
+	p.displayRelays(pp.Relays)
+}
+
+func (p *pasteVars) displayRelays(relays []string) {
+	if len(relays) > 0 {
+		relaysLabel := qt.NewQLabel2()
+		relaysLabel.SetText("relays:")
+		p.outputVBox.AddWidget(relaysLabel.QWidget)
+		relaysVBox := qt.NewQVBoxLayout2()
+		for i := 0; i < len(relays); i += 5 {
+			rowHBox := qt.NewQHBoxLayout2()
+			for j := 0; j < 5 && i+j < len(relays); j++ {
+				relayEdit := qt.NewQLineEdit(window.QWidget)
+				relayEdit.SetText(relays[i+j])
+				relayEdit.SetReadOnly(true)
+				rowHBox.AddWidget(relayEdit.QWidget)
+			}
+			relaysVBox.AddLayout(rowHBox.QLayout)
+		}
+		p.outputVBox.AddLayout(relaysVBox.QLayout)
+	}
+}
+
+func (p *pasteVars) displayAddressPointer(ap nostr.EntityPointer) {
+	kindLabel := qt.NewQLabel2()
+	kindLabel.SetText("kind:")
+	p.outputVBox.AddWidget(kindLabel.QWidget)
+	kindEdit := qt.NewQLineEdit(window.QWidget)
+	kindEdit.SetText(fmt.Sprintf("%d", ap.Kind))
+	kindEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(kindEdit.QWidget)
+
+	p.displayPubKey(ap.PublicKey)
+
+	identifierLabel := qt.NewQLabel2()
+	identifierLabel.SetText("identifier:")
+	p.outputVBox.AddWidget(identifierLabel.QWidget)
+	identifierEdit := qt.NewQLineEdit(window.QWidget)
+	identifierEdit.SetText(ap.Identifier)
+	identifierEdit.SetReadOnly(true)
+	p.outputVBox.AddWidget(identifierEdit.QWidget)
+
+	p.displayRelays(ap.Relays)
+}
+
+func (p *pasteVars) displayNip05(identifier string) {
+	mainthread.Wait(func() {
+		label := qt.NewQLabel2()
+		label.SetText("nip05: " + identifier)
+		p.outputVBox.AddWidget(label.QWidget)
+	})
+
+	// try to query
+	if paste.nip05ctxCancel != nil {
+		paste.nip05ctxCancel()
+	}
+	nip05ctx, cancel := context.WithTimeoutCause(ctx, time.Second*3, paste.nip05ctxAbort)
+	paste.nip05ctxCancel = cancel
+	defer cancel()
+	pp, err := nip05.QueryIdentifier(nip05ctx, identifier)
+	if err != nil && err != paste.nip05ctxAbort {
+		mainthread.Wait(func() {
+			errorLabel := qt.NewQLabel2()
+			errorLabel.SetText("failed to query nip05: " + err.Error())
+			p.outputVBox.AddWidget(errorLabel.QWidget)
+		})
+		return
+	}
+
+	mainthread.Wait(func() {
+		nprofileLabel := qt.NewQLabel2()
+		nprofileLabel.SetText("nprofile")
+		p.outputVBox.AddWidget(nprofileLabel.QWidget)
+		nprofileEdit := qt.NewQLineEdit(window.QWidget)
+		nprofileEdit.SetText(nip19.EncodeNprofile(pp.PublicKey, pp.Relays))
+		nprofileEdit.SetReadOnly(true)
+		p.outputVBox.AddWidget(nprofileEdit.QWidget)
+
+		p.displayProfilePointer(*pp)
+		p.displayPointerTag(*pp)
+	})
+}
+
+func (p *pasteVars) displayEventButton(evt nostr.Event) {
+	button := qt.NewQPushButton5("event", window.QWidget)
+	button.OnClicked(func() {
+		// populate event tab
+		event.kindSpin.SetValue(int(evt.Kind))
+		event.contentEdit.SetPlainText(evt.Content)
+		// created_at
+		dt := qt.NewQDateTime()
+		dt.SetMSecsSinceEpoch(int64(evt.CreatedAt) * 1000)
+		event.createdAtEdit.SetDateTime(dt)
+		// tags
+		// clear existing
+		for len(event.tagRows) > 1 {
+			// remove last row
+			lastRow := event.tagRows[len(event.tagRows)-1]
+			for _, edit := range lastRow {
+				edit.DeleteLater()
+			}
+			event.tagRows = event.tagRows[:len(event.tagRows)-1]
+		}
+		// set tags
+		for i, tag := range evt.Tags {
+			if i >= len(event.tagRows) {
+				// add more rows if needed
+				// but for simplicity, just set what we can
+				break
+			}
+			for j, value := range tag {
+				if j >= len(event.tagRows[i]) {
+					break
+				}
+				event.tagRows[i][j].SetText(value)
+			}
+		}
+		// switch to event tab
+		tabWidget.SetCurrentIndex(0) // assuming event is first
+	})
+	p.outputVBox.AddWidget(button.QWidget)
+}
+
+func (p *pasteVars) displayFilterButton(filt nostr.Filter) {
+	button := qt.NewQPushButton5("filter", window.QWidget)
+	button.OnClicked(func() {
+		// populate req tab
+		// authors
+		for i, author := range filt.Authors {
+			if i < len(req.authorsEdits) {
+				req.authorsEdits[i].SetText(nip19.EncodeNpub(author))
+			}
+		}
+		// ids
+		for i, id := range filt.IDs {
+			if i < len(req.idsEdits) {
+				req.idsEdits[i].SetText(id.String())
+			}
+		}
+		// kinds
+		for i, kind := range filt.Kinds {
+			if i < len(req.kindsEdits) {
+				req.kindsEdits[i].SetText(fmt.Sprintf("%d", kind))
+			}
+		}
+		// since
+		if filt.Since != 0 {
+			dt := qt.NewQDateTime()
+			dt.SetMSecsSinceEpoch(int64(filt.Since) * 1000)
+			req.sinceEdit.SetDateTime(dt)
+		}
+		// until
+		if filt.Until != 0 {
+			dt := qt.NewQDateTime()
+			dt.SetMSecsSinceEpoch(int64(filt.Until) * 1000)
+			req.untilEdit.SetDateTime(dt)
+		}
+		// limit
+		req.limitSpin.SetValue(filt.Limit)
+		// switch to req tab
+		tabWidget.SetCurrentIndex(1) // assuming req is second
+	})
+	p.outputVBox.AddWidget(button.QWidget)
+}