Protocol Explorer pricing
Protocol Explorer keeps four protocols free so you can judge the tool before paying. One payment of $4.99 opens the rest of the library permanently — there is no subscription, no seat count and no renewal.
- HTTP, HTTPS, TCP and UDP lessons
- Protocol overview for all 33 protocols
- First three steps of each free exchange
- Network and sequence views
- Remaining 29 protocols
- Byte-level inspector on later packets
- All 33 protocols unlocked
- Every step, including retransmits, SACK, fragmentation and NAT rewrites
- Byte-level header inspector on every packet
- Exit-path scenarios: QUIC, BGP, WireGuard, WPA3, Modbus
- Progress synced across devices
- Future protocols added to the library
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What the $4.99 actually pays for
The animation engine, the packet table and the inspector are the same in both plans. What the Pro pass buys is the content behind them: the remaining 29 scenarios, the later steps that carry the interesting failures — a dropped segment, a SACK-driven retransmit, a fragmented datagram, a NAT rewrite — and the byte-level decoding that goes with them. If you only need to explain a TCP handshake, the free lessons already cover it.
Side by side
| Capability | Free | Pro |
|---|---|---|
| Protocol overviews | All 33 | All 33 |
| Full lessons | HTTP, HTTPS, TCP, UDP | All 33 |
| Steps per lesson | First 3 | All |
| Packet inspector | Preview bytes | Every field decoded |
| Progress sync | This browser | Every signed-in device |
| Billing | — | $4.99 once |
Questions about the Protocol Explorer pass
- Is this a subscription?
- No. It is a single $4.99 payment and the licence does not expire.
- Do I lose access if I clear my browser?
- No. Sign in with the same email and the licence is restored from our records.
- Can I use it on more than one device?
- Yes. Any device where you sign in with the purchasing email gets Pro.
- Refunds?
- Write to us within 14 days of purchase and we refund without argument. See the terms.