Packet Tester: TCP UDP Socket

Packet Tester is a complete network lab in your pocket. Send TCP and UDP packets, run a local server, test 28 protocols and build custom binary packets, right from your phone. No root, no laptop.

Built for network engineers, IoT and embedded developers, QA testers, VoIP engineers, students and anyone who needs to see what really goes over the wire.

SOCKET TESTER
• TCP client: connect to any host and port, send text, HEX, Base64 or binary and watch every TX/RX byte live
• UDP sender with per-packet response timing, broadcast and multicast
• TCP server and UDP listener: let other devices connect to your phone and echo or auto-reply
• TLS / SSL tester: handshake details, cipher, full certificate chain and validity (Pro)
• DTLS 1.2 tester with certificate or PSK (Pro)
• Repeat and stress tests with RTT, min/avg/max, jitter and timeouts (Pro)

28 PROTOCOL TESTERS
Ready-made testers speak the protocol for you and explain the reply in plain words:
• Network: DNS (A, AAAA, MX, TXT, NS, SOA, PTR, SRV, CAA), ICMP ping, DHCP info, ARP, NTP
• Web: HTTP / HTTPS requests with headers, body and timing
• Mail and services: SMTP, POP3, IMAP, Telnet, RTSP, Redis, MySQL, PostgreSQL
• VoIP: SIP OPTIONS / REGISTER probes
• Pro protocol packs: MQTT, WebSocket, CoAP, Modbus TCP, SNMP, STUN, TURN, RTP, LDAP

PACKET BUILDER
• Design packets field by field: integers, floats, strings, HEX, constants and payloads
• Big or little endian per packet or per field
• Calculated length fields and CRC / checksum fields (CRC-8, CRC-16, CRC-32 and more) (Pro)
• Live validation and a structured byte map, then send it over TCP or UDP in one tap

PACKET INSPECTOR AND DECODERS
• Paste HEX and see every byte with offsets and ASCII
• Decode with built-in protocol decoders or your own custom protocol definitions (Pro)
• Import and export protocol definitions as JSON

AUTOMATION, HISTORY AND REPORTS
• Chain tests into recipes and re-run them with one tap (Pro)
• Every test is saved in history, searchable and re-runnable
• Templates and favourites for the tests you use most
• Export reports and logs as TXT, JSON or CSV (Pro)

TOOLS
• Checksum / CRC calculator, data converter (HEX, text, Base64, numbers)
• Network info: local IP, gateway, DNS servers and Wi-Fi details

PRIVATE BY DESIGN
Tests run directly from your device to the host you choose. Your hosts, payloads, logs and history stay on your phone. Credentials are masked in logs and reports by default.

PACKET TESTER PRO: ONE-TIME PURCHASE
Unlock TLS and DTLS testers, protocol packs, the advanced packet builder, custom protocols, automation, export, and remove all ads. Pay once, no subscription.

Only test devices and networks you own or have permission to test.

Recent changes:
First release of Packet Tester:
• TCP/UDP socket tester, TCP server and UDP listener
• 28 protocol testers including DNS, HTTP, SIP, NTP, MQTT and Modbus
• Packet Builder with CRC fields and Packet Inspector with decoders
• Automation, history, templates and export