Custom Arguments

🔧 Custom Arguments Reference

Complete reference for Custom mode in GoodByeDPI GUI — every flag, what it does, and when to use it.

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📖 Overview

In Custom mode, you supply your own arguments. These are passed directly to goodbyedpi.exe.

Format: flags separated by spaces, like a normal command line:

-f 2 -e 40 --native-frag --reverse-frag

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🎯 Mode Shortcuts (Presets)

Simplest way to get started — a single number enables a whole preset.

Flag	Description	Badge
-1	Legacy: most compatible
-2	Legacy: better HTTPS speed
-3	Legacy: HTTP + HTTPS
-4	Legacy: best speed
-5	Modern: auto-TTL, stable	⭐ Recommended
-6	Modern: fake SEQ, fast	⭐ Recommended
-7	Modern: fake checksum
-8	Modern: fake SEQ + checksum
-9	Modern: full suite (default)	🎯 Default

⚠️ Don't combine multiple modesets. Pick one.

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⚙️ Basic Flags

Flag	Description
-p	Block passive DPI
-q	Block QUIC / HTTP3
-r	Replace Host header with hoSt
-s	Remove space after Host: header
-m	Mix Host header case
-w	Find HTTP on all processed ports
--max-payload	Skip payloads larger than 1200 bytes (recommended)

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✂️ Fragmentation Flags

Control how packets are split to evade DPI.

Flag	Description	Badge
-f <n>	HTTP fragmentation value
-k <n>	HTTP keep-alive fragmentation
-n	Don't wait for first ACK (needs -k)
-e <n>	HTTPS fragmentation value
--native-frag	Split packets, don't shrink window	⭐ Recommended
--reverse-frag	Send fragments in reverse order	⭐ Recommended
--frag-by-sni	Fragment right before SNI value

💡 Typical combination: -f 2 -e 40 --native-frag --reverse-frag

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🎭 Fake Request Flags

Send fake packets to confuse DPI before the real one arrives.

Flag	Description	Badge
--wrong-seq	Fake packet with past SEQ/ACK	⭐ Recommended
--wrong-chksum	Fake packet with bad TCP checksum
--set-ttl <n>	Fake request with fixed TTL	⚠ Dangerous
--auto-ttl	Auto-detect TTL	⚠ Dangerous
--min-ttl <n>	Min TTL distance for fake request
--fake-gen <n>	N random fake packets (max 30)
--fake-resend <n>	Send each fake packet N times
--fake-with-sni <domain>	Fake Firefox TLS with given SNI

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🧪 Advanced Flags

For power users and edge cases.

Flag	Description
--port <n>	Fragment additional TCP port
--ip-id <n>	Handle additional IP ID
--blacklist <file>	Apply tricks only to hosts in file
--allow-no-sni	Apply tricks even if SNI not detected
--dns-addr <ip>	Redirect UDP DNS to IP
--dns-port <n>	Redirect UDP DNS to port
--dnsv6-addr <ip>	Redirect UDPv6 DNS to IPv6
--dnsv6-port <n>	Redirect UDPv6 DNS to port
--dns-verb	Verbose DNS redirection logs

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🍳 Ready-to-Use Recipes

🥇 The Classic (most common)

-6

🥈 Fragmentation Combo

-f 2 -e 40 --native-frag --reverse-frag --max-payload

🥉 Aggressive Bypass

-9 --fake-gen 5 --fake-resend 2 --auto-ttl --min-ttl 3

🔒 With Custom DNS (Cloudflare)

-6 --dns-addr 1.1.1.1 --dns-port 53 --dnsv6-addr 2606:4700:4700::1111 --dnsv6-port 53

🎯 SNI-Targeted

-f 2 -e 40 --frag-by-sni --reverse-frag

🚀 Maximum Compatibility

-f 2 -e 40 -k 2 -n --native-frag --reverse-frag --wrong-seq --max-payload

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✅ Live Validation

While you type, GoodByeDPI GUI checks your arguments in real time.

What it catches

Type	Example
❌ Typos	--wrong-seqq instead of --wrong-seq
❌ Missing values	-f with no number after it
❌ Unknown flags	--doesnt-exist
⚠ Redundant combos	-a -s together
⚠ Conflicts	--wrong-seq --wrong-chksum --set-ttl
⚠ Ineffective flags	-n without -k

Indicator colors:

• 🟢 ✓ — All good
• 🟡 ⚠ — Warnings only
• 🔴 ✕ — Errors

Hover over the indicator for the full list.

💡 Even with errors, you can still click Start — a confirmation dialog will appear.

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📖 Built-in Arguments Guide

Click ? next to the Custom args field to open the Arguments Guide:

• 5 tabs: Presets, Basic, Fragmentation, Fake Request, Advanced
• Live search: type to filter all flags
• One-click add: press + to append a flag
• Presets tab: + replaces the entire line
• Badges tell you which flags are recommended / dangerous

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🧪 Testing Strategy

When trying a new Custom combination:

1. Stop GoodByeDPI
2. Enter your new arguments
3. Start
4. Open a browser and visit a previously blocked site
5. Wait 10-15 seconds — TLS handshakes can be slow on first connect
6. If it fails → check the log for errors
7. Try a different combination

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🚫 Common Mistakes

❌ Don't	✅ Do
Combine -5 -6 -9	Pick one modeset
Forget the value: -f	Always: -f 2
Use --set-ttl and --auto-ttl	Pick one
Add --dns-port without --dns-addr	Pair them
Run with a VPN	Disable VPN first

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🔗 External Reference

• Official GoodbyeDPI README — source of truth
• GoodbyeDPI Issues — community troubleshooting

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Next: Run into a problem? See Troubleshooting 🩺