diff --git a/explorer/package-lock.json b/explorer/package-lock.json
index 1223a9eb1b30f7..e2c2a87523f924 100644
--- a/explorer/package-lock.json
+++ b/explorer/package-lock.json
@@ -1595,6 +1595,14 @@
         "@babel/types": "^7.3.0"
       }
     },
+    "@types/bs58": {
+      "version": "4.0.1",
+      "resolved": "https://registry.npmjs.org/@types/bs58/-/bs58-4.0.1.tgz",
+      "integrity": "sha512-yfAgiWgVLjFCmRv8zAcOIHywYATEwiTVccTLnRp6UxTNavT55M9d/uhK3T03St/+8/z/wW+CRjGKUNmEqoHHCA==",
+      "requires": {
+        "base-x": "^3.0.6"
+      }
+    },
     "@types/color-name": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/@types/color-name/-/color-name-1.1.1.tgz",
diff --git a/explorer/package.json b/explorer/package.json
index 53abcc90e39f1a..12c79374911eed 100644
--- a/explorer/package.json
+++ b/explorer/package.json
@@ -7,11 +7,13 @@
     "@testing-library/jest-dom": "^4.2.4",
     "@testing-library/react": "^9.3.2",
     "@testing-library/user-event": "^7.1.2",
+    "@types/bs58": "^4.0.1",
     "@types/jest": "^24.0.0",
     "@types/node": "^12.0.0",
     "@types/react": "^16.9.0",
     "@types/react-dom": "^16.9.0",
     "bootstrap": "^4.4.1",
+    "bs58": "^4.0.1",
     "node-sass": "^4.13.1",
     "prettier": "^1.19.1",
     "react": "^16.13.0",
diff --git a/explorer/src/components/NetworkModal.tsx b/explorer/src/components/NetworkModal.tsx
index b86df65f07c9e9..cb0664478c9c22 100644
--- a/explorer/src/components/NetworkModal.tsx
+++ b/explorer/src/components/NetworkModal.tsx
@@ -9,6 +9,7 @@ import {
   NETWORKS,
   Network
 } from "../providers/network";
+import { assertUnreachable } from "../utils";
 
 type Props = {
   show: boolean;
@@ -103,6 +104,8 @@ function NetworkToggle() {
     case NetworkStatus.Failure:
       activeSuffix = "danger";
       break;
+    default:
+      assertUnreachable(status);
   }
 
   return (
diff --git a/explorer/src/components/TransactionsCard.tsx b/explorer/src/components/TransactionsCard.tsx
index 7223d653f1f6b4..30188fdfce4bde 100644
--- a/explorer/src/components/TransactionsCard.tsx
+++ b/explorer/src/components/TransactionsCard.tsx
@@ -1,12 +1,47 @@
 import React from "react";
 import {
   useTransactions,
+  useTransactionsDispatch,
+  checkTransactionStatus,
+  ActionType,
   Transaction,
   Status
 } from "../providers/transactions";
+import bs58 from "bs58";
+import { assertUnreachable } from "../utils";
+import { useNetwork } from "../providers/network";
 
 function TransactionsCard() {
-  const { transactions } = useTransactions();
+  const { transactions, idCounter } = useTransactions();
+  const dispatch = useTransactionsDispatch();
+  const signatureInput = React.useRef<HTMLInputElement>(null);
+  const [error, setError] = React.useState("");
+  const { url } = useNetwork();
+
+  const onNew = (signature: string) => {
+    if (signature.length === 0) return;
+    try {
+      const length = bs58.decode(signature).length;
+      if (length > 64) {
+        setError("Signature is too short");
+        return;
+      } else if (length < 64) {
+        setError("Signature is too short");
+        return;
+      }
+    } catch (err) {
+      setError(`${err}`);
+      return;
+    }
+
+    dispatch({ type: ActionType.InputSignature, signature });
+    checkTransactionStatus(dispatch, idCounter + 1, signature, url);
+
+    const inputEl = signatureInput.current;
+    if (inputEl) {
+      inputEl.value = "";
+    }
+  };
 
   return (
     <div className="card">
@@ -16,6 +51,9 @@ function TransactionsCard() {
         <table className="table table-sm table-nowrap card-table">
           <thead>
             <tr>
+              <th className="text-muted text-center">
+                <span className="fe fe-hash"></span>
+              </th>
               <th className="text-muted">Status</th>
               <th className="text-muted">Signature</th>
               <th className="text-muted">Confirmations</th>
@@ -23,9 +61,36 @@ function TransactionsCard() {
             </tr>
           </thead>
           <tbody className="list">
-            {Object.values(transactions).map(transaction =>
-              renderTransactionRow(transaction)
-            )}
+            <tr>
+              <td>
+                <span className="badge badge-soft-dark badge-pill">
+                  {idCounter + 1}
+                </span>
+              </td>
+
+              <td>
+                <span className={`badge badge-soft-primary`}>New</span>
+              </td>
+              <td>
+                <input
+                  type="text"
+                  onInput={() => setError("")}
+                  onKeyDown={e =>
+                    e.keyCode === 13 && onNew(e.currentTarget.value)
+                  }
+                  onSubmit={e => onNew(e.currentTarget.value)}
+                  ref={signatureInput}
+                  className={`form-control text-signature text-monospace ${
+                    error ? "is-invalid" : ""
+                  }`}
+                  placeholder="abcd..."
+                />
+                {error ? <div className="invalid-feedback">{error}</div> : null}
+              </td>
+              <td>-</td>
+              <td>-</td>
+            </tr>
+            {transactions.map(transaction => renderTransactionRow(transaction))}
           </tbody>
         </table>
       </div>
@@ -65,22 +130,29 @@ const renderTransactionRow = (transaction: Transaction) => {
       statusClass = "danger";
       statusText = "Failed";
       break;
-    case Status.Pending:
+    case Status.Missing:
       statusClass = "warning";
-      statusText = "Pending";
+      statusText = "Not Found";
       break;
+    default:
+      return assertUnreachable(transaction.status);
   }
 
   return (
     <tr key={transaction.signature}>
+      <td>
+        <span className="badge badge-soft-dark badge-pill">
+          {transaction.id}
+        </span>
+      </td>
       <td>
         <span className={`badge badge-soft-${statusClass}`}>{statusText}</span>
       </td>
       <td>
         <code>{transaction.signature}</code>
       </td>
-      <td>TODO</td>
-      <td>TODO</td>
+      <td>-</td>
+      <td>-</td>
     </tr>
   );
 };
diff --git a/explorer/src/providers/network.tsx b/explorer/src/providers/network.tsx
index 498da862e57935..e4f5e0ca7a892a 100644
--- a/explorer/src/providers/network.tsx
+++ b/explorer/src/providers/network.tsx
@@ -133,7 +133,7 @@ export function NetworkProvider({ children }: NetworkProviderProps) {
   );
 }
 
-export function networkUrl(network: Network, customUrl: string) {
+export function networkUrl(network: Network, customUrl: string): string {
   switch (network) {
     case Network.Devnet:
       return DEVNET_URL;
diff --git a/explorer/src/providers/transactions.tsx b/explorer/src/providers/transactions.tsx
index 4aca742259128a..ada85231e95a18 100644
--- a/explorer/src/providers/transactions.tsx
+++ b/explorer/src/providers/transactions.tsx
@@ -8,13 +8,18 @@ export enum Status {
   CheckFailed,
   Success,
   Failure,
-  Pending
+  Missing
+}
+
+enum Source {
+  Url,
+  Input
 }
 
 export interface Transaction {
   id: number;
   status: Status;
-  recent: boolean;
+  source: Source;
   signature: TransactionSignature;
 }
 
@@ -24,20 +29,52 @@ interface State {
   transactions: Transactions;
 }
 
+export enum ActionType {
+  UpdateStatus,
+  InputSignature
+}
+
 interface UpdateStatus {
+  type: ActionType.UpdateStatus;
   id: number;
   status: Status;
 }
 
-type Action = UpdateStatus;
+interface InputSignature {
+  type: ActionType.InputSignature;
+  signature: TransactionSignature;
+}
+
+type Action = UpdateStatus | InputSignature;
 type Dispatch = (action: Action) => void;
 
 function reducer(state: State, action: Action): State {
-  let transaction = state.transactions[action.id];
-  if (transaction) {
-    transaction = { ...transaction, status: action.status };
-    const transactions = { ...state.transactions, [action.id]: transaction };
-    return { ...state, transactions };
+  switch (action.type) {
+    case ActionType.InputSignature: {
+      const idCounter = state.idCounter + 1;
+      const transactions = {
+        ...state.transactions,
+        [idCounter]: {
+          id: idCounter,
+          status: Status.Checking,
+          source: Source.Input,
+          signature: action.signature
+        }
+      };
+      return { ...state, transactions, idCounter };
+    }
+    case ActionType.UpdateStatus: {
+      let transaction = state.transactions[action.id];
+      if (transaction) {
+        transaction = { ...transaction, status: action.status };
+        const transactions = {
+          ...state.transactions,
+          [action.id]: transaction
+        };
+        return { ...state, transactions };
+      }
+      break;
+    }
   }
   return state;
 }
@@ -51,7 +88,7 @@ function initState(): State {
       transactions[id] = {
         id,
         status: Status.Checking,
-        recent: true,
+        source: Source.Url,
         signature
       };
       return transactions;
@@ -72,9 +109,8 @@ export function TransactionsProvider({ children }: TransactionsProviderProps) {
 
   // Check transaction statuses on startup and whenever network updates
   React.useEffect(() => {
-    const connection = new Connection(url);
     Object.values(state.transactions).forEach(tx => {
-      checkTransactionStatus(dispatch, tx, connection);
+      checkTransactionStatus(dispatch, tx.id, tx.signature, url);
     });
   }, [status, url]); // eslint-disable-line react-hooks/exhaustive-deps
 
@@ -89,23 +125,24 @@ export function TransactionsProvider({ children }: TransactionsProviderProps) {
 
 export async function checkTransactionStatus(
   dispatch: Dispatch,
-  transaction: Transaction,
-  connection: Connection
+  id: number,
+  signature: TransactionSignature,
+  url: string
 ) {
-  const id = transaction.id;
   dispatch({
+    type: ActionType.UpdateStatus,
     status: Status.Checking,
     id
   });
 
   let status;
   try {
-    const signatureStatus = await connection.getSignatureStatus(
-      transaction.signature
+    const signatureStatus = await new Connection(url).getSignatureStatus(
+      signature
     );
 
     if (signatureStatus === null) {
-      status = Status.Pending;
+      status = Status.Missing;
     } else if ("Ok" in signatureStatus) {
       status = Status.Success;
     } else {
@@ -115,7 +152,7 @@ export async function checkTransactionStatus(
     console.error("Failed to check transaction status", error);
     status = Status.CheckFailed;
   }
-  dispatch({ status, id });
+  dispatch({ type: ActionType.UpdateStatus, status, id });
 }
 
 export function useTransactions() {
@@ -125,7 +162,12 @@ export function useTransactions() {
       `useTransactions must be used within a TransactionsProvider`
     );
   }
-  return context;
+  return {
+    idCounter: context.idCounter,
+    transactions: Object.values(context.transactions).sort((a, b) =>
+      a.id <= b.id ? 1 : -1
+    )
+  };
 }
 
 export function useTransactionsDispatch() {
diff --git a/explorer/src/scss/_solana.scss b/explorer/src/scss/_solana.scss
index 57553e3d752089..995c85ab17ff44 100644
--- a/explorer/src/scss/_solana.scss
+++ b/explorer/src/scss/_solana.scss
@@ -32,4 +32,12 @@ code {
       cursor: text;
     }
   }
+}
+
+.text-signature {
+  font-size: 85%;
+}
+
+input.text-signature {
+  padding: 0 0.75rem
 }
\ No newline at end of file
diff --git a/explorer/src/utils.ts b/explorer/src/utils.ts
index fc96ca2a2b6d0c..bb9fb4d9739244 100644
--- a/explorer/src/utils.ts
+++ b/explorer/src/utils.ts
@@ -10,3 +10,7 @@ export function findGetParameter(parameterName: string): string | null {
     });
   return result;
 }
+
+export function assertUnreachable(x: never): never {
+  throw new Error("Unreachable!");
+}