diff --git a/api.go b/api.go
index 08df4889c..5f5b3807f 100644
--- a/api.go
+++ b/api.go
@@ -45,6 +45,7 @@ type API struct {
 	holder  *Holder
 	cluster *cluster
 	server  *Server
+	tracker *queryTracker
 
 	importWorkersWG      sync.WaitGroup
 	importWorkerPoolSize int
@@ -95,6 +96,8 @@ func NewAPI(opts ...apiOption) (*API, error) {
 		}()
 	}
 
+	api.tracker = newQueryTracker()
+
 	return api, nil
 }
 
@@ -130,6 +133,7 @@ func (api *API) validate(f apiMethod) error {
 func (api *API) Close() error {
 	close(api.importWork)
 	api.importWorkersWG.Wait()
+	api.tracker.Stop()
 	return nil
 }
 
@@ -146,6 +150,7 @@ func (api *API) Query(ctx context.Context, req *QueryRequest) (QueryResponse, er
 	if err != nil {
 		return QueryResponse{}, errors.Wrap(err, "parsing")
 	}
+	defer api.tracker.Finish(api.tracker.Start(req.Query))
 	execOpts := &execOptions{
 		Remote:          req.Remote,
 		Profile:         req.Profile,
@@ -1701,6 +1706,13 @@ func (api *API) GetTransaction(ctx context.Context, id string, remote bool) (*Tr
 	return t, err
 }
 
+func (api *API) ActiveQueries(ctx context.Context) ([]ActiveQueryStatus, error) {
+	if err := api.validate(apiActiveQueries); err != nil {
+		return nil, errors.Wrap(err, "validating api method")
+	}
+	return api.tracker.ActiveQueries(), nil
+}
+
 type serverInfo struct {
 	ShardWidth       uint64 `json:"shardWidth"`
 	Memory           uint64 `json:"memory"`
@@ -1752,6 +1764,7 @@ const (
 	apiFinishTransaction
 	apiTransactions
 	apiGetTransaction
+	apiActiveQueries
 )
 
 var methodsCommon = map[apiMethod]struct{}{
@@ -1791,4 +1804,5 @@ var methodsNormal = map[apiMethod]struct{}{
 	apiFinishTransaction:    {},
 	apiTransactions:         {},
 	apiGetTransaction:       {},
+	apiActiveQueries:        {},
 }
diff --git a/http/handler.go b/http/handler.go
index 12773f3ee..f6e0ac001 100644
--- a/http/handler.go
+++ b/http/handler.go
@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"io"
 	"math"
+	"mime"
 	"net"
 	"net/http"
 	_ "net/http/pprof" // Imported for its side-effect of registering pprof endpoints with the server.
@@ -358,6 +359,7 @@ func newRouter(handler *Handler) *mux.Router {
 	router.HandleFunc("/transaction/{id}", handler.handlePostTransaction).Methods("POST").Name("PostTransaction")
 	router.HandleFunc("/transaction/{id}/finish", handler.handlePostFinishTransaction).Methods("POST").Name("PostFinishTransaction")
 	router.HandleFunc("/transactions", handler.handleGetTransactions).Methods("GET").Name("GetTransactions")
+	router.HandleFunc("/queries", handler.handleGetActiveQueries).Methods("GET").Name("GetActiveQueries")
 	router.HandleFunc("/version", handler.handleGetVersion).Methods("GET").Name("GetVersion")
 
 	// /internal endpoints are for internal use only; they may change at any time.
@@ -475,9 +477,33 @@ func (h *Handler) handleHome(w http.ResponseWriter, _ *http.Request) {
 // headers are present, but none of them are "application/json"
 // (or any matching wildcard). Otherwise returns true.
 func validHeaderAcceptJSON(header http.Header) bool {
+	return validHeaderAcceptType(header, "application", "json")
+}
+
+func validHeaderAcceptType(header http.Header, typ, subtyp string) bool {
 	if v, found := header["Accept"]; found {
 		for _, v := range v {
-			if v == "application/json" || v == "*/*" || v == "*/json" || v == "application/*" {
+			t, _, err := mime.ParseMediaType(v)
+			if err != nil {
+				switch err {
+				case mime.ErrInvalidMediaParameter:
+					// This is an optional feature, so we can keep going anyway.
+				default:
+					continue
+				}
+			}
+			spl := strings.SplitN(t, "/", 2)
+			if len(spl) < 2 {
+				continue
+			}
+			switch {
+			case spl[0] == typ && spl[1] == subtyp:
+				return true
+			case spl[0] == "*" && spl[1] == subtyp:
+				return true
+			case spl[0] == typ && spl[1] == "*":
+				return true
+			case spl[0] == "*" && spl[1] == "*":
 				return true
 			}
 		}
@@ -835,6 +861,52 @@ func (h *Handler) handlePostIndexAttrDiff(w http.ResponseWriter, r *http.Request
 	}
 }
 
+func (h *Handler) handleGetActiveQueries(w http.ResponseWriter, r *http.Request) {
+	var rtype string
+	switch {
+	case validHeaderAcceptType(r.Header, "text", "plain"):
+		rtype = "text/plain"
+	case validHeaderAcceptJSON(r.Header):
+		rtype = "application/json"
+	default:
+		http.Error(w, "no acceptable response type selected", http.StatusNotAcceptable)
+		return
+	}
+	queries, err := h.api.ActiveQueries(r.Context())
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	w.Header().Set("Content-Type", rtype)
+	switch rtype {
+	case "text/plain":
+		durations := make([]string, len(queries))
+		for i, q := range queries {
+			durations[i] = q.Age.String()
+		}
+		var maxlen int
+		for _, l := range durations {
+			if len(l) > maxlen {
+				maxlen = len(l)
+			}
+		}
+		for i, q := range queries {
+			_, err := fmt.Fprintf(w, "%*s%q\n", -(maxlen + 2), durations[i], q.Query)
+			if err != nil {
+				h.logger.Printf("sending GetActiveQueries response: %s", err)
+				return
+			}
+		}
+		if _, err := w.Write([]byte{'\n'}); err != nil {
+			h.logger.Printf("sending GetActiveQueries response: %s", err)
+		}
+	case "application/json":
+		if err := json.NewEncoder(w).Encode(queries); err != nil {
+			h.logger.Printf("encoding GetActiveQueries response: %s", err)
+		}
+	}
+}
+
 type postIndexAttrDiffRequest struct {
 	Blocks []pilosa.AttrBlock `json:"blocks"`
 }
diff --git a/tracker.go b/tracker.go
new file mode 100644
index 000000000..af5788137
--- /dev/null
+++ b/tracker.go
@@ -0,0 +1,125 @@
+// Copyright 2020 Pilosa Corp.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pilosa
+
+import (
+	"sort"
+	"sync"
+	"time"
+)
+
+type ActiveQueryStatus struct {
+	Query string        `json:"query"`
+	Age   time.Duration `json:"age"`
+}
+
+type activeQuery struct {
+	query   string
+	started time.Time
+}
+
+type queryStatusUpdate struct {
+	q   *activeQuery
+	end bool
+}
+
+type queryTracker struct {
+	updates chan<- queryStatusUpdate
+	checks  chan<- chan<- []*activeQuery
+	wg      sync.WaitGroup
+	stop    chan struct{}
+}
+
+func newQueryTracker() *queryTracker {
+	done := make(chan struct{})
+	updates := make(chan queryStatusUpdate, 128)
+	checks := make(chan chan<- []*activeQuery)
+	tracker := &queryTracker{
+		updates: updates,
+		checks:  checks,
+		stop:    done,
+	}
+	tracker.wg.Add(1)
+	go func() {
+		defer tracker.wg.Done()
+
+		activeQueries := make(map[*activeQuery]struct{})
+
+		for {
+			select {
+			case update := <-updates:
+				if update.end {
+					delete(activeQueries, update.q)
+				} else {
+					activeQueries[update.q] = struct{}{}
+				}
+			case check := <-checks:
+				out := make([]*activeQuery, len(activeQueries))
+				i := 0
+				for q := range activeQueries {
+					out[i] = q
+					i++
+				}
+				check <- out
+				close(check)
+			case <-done:
+				return
+			}
+		}
+	}()
+	return tracker
+}
+
+func (t *queryTracker) Start(query string) *activeQuery {
+	now := time.Now()
+	q := &activeQuery{query, now}
+	t.updates <- queryStatusUpdate{q, false}
+	return q
+}
+
+func (t *queryTracker) Finish(q *activeQuery) {
+	t.updates <- queryStatusUpdate{q, true}
+}
+
+func (t *queryTracker) ActiveQueries() []ActiveQueryStatus {
+	ch := make(chan []*activeQuery, 1)
+	t.checks <- ch
+	queries := <-ch
+	sort.Slice(queries, func(i, j int) bool {
+		switch {
+		case queries[i].started.Before(queries[j].started):
+			return true
+		case queries[i].started.After(queries[j].started):
+			return false
+		case queries[i].query < queries[j].query:
+			return true
+		case queries[i].query > queries[j].query:
+			return false
+		default:
+			return false
+		}
+	})
+	now := time.Now()
+	out := make([]ActiveQueryStatus, len(queries))
+	for i, v := range queries {
+		out[i] = ActiveQueryStatus{v.query, now.Sub(v.started)}
+	}
+	return out
+}
+
+func (t *queryTracker) Stop() {
+	close(t.stop)
+	t.wg.Wait()
+}
diff --git a/tracker_test.go b/tracker_test.go
new file mode 100644
index 000000000..80f6f84f2
--- /dev/null
+++ b/tracker_test.go
@@ -0,0 +1,42 @@
+// Copyright 2020 Pilosa Corp.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pilosa
+
+import "testing"
+
+func TestQueryTracker(t *testing.T) {
+	tracker := newQueryTracker()
+	defer tracker.Stop()
+
+	if queries := tracker.ActiveQueries(); len(queries) > 0 {
+		t.Fatalf("expected no active queries; found %v", queries)
+	}
+
+	qs := tracker.Start("test query")
+
+	var queries []ActiveQueryStatus
+	for len(queries) < 1 {
+		queries = tracker.ActiveQueries()
+	}
+	if len(queries) > 1 || queries[0].Query != "test query" {
+		t.Fatalf("unexpected queries: %v", queries)
+	}
+
+	tracker.Finish(qs)
+
+	for len(queries) > 0 {
+		queries = tracker.ActiveQueries()
+	}
+}