iPhone Secret Codes & Hidden Tricks 2026
iPhone has hidden 'secret codes' that unlock diagnostic info, change call forwarding, even show signal in dB. Here are the codes that actually work in 2026.
⚡ Diagnostic Hardware
When secret codes aren't enough.
Service kit for diagnostics
Cost Breakdown — All Options
| Where | Cost | Wait | Notes |
|---|---|---|---|
| Field Test (signal in dB) | *3001#12345#* | Hidden mode | More accurate than bars |
| IMEI display | *#06# | Universal | All phones |
| Check call forwarding | *#21# | All phones | See active redirects |
| Cancel all forwarding | ##002# | All phones | Reset call forward |
| Voice quality on call | *#92702689# | Older iPhones | Diagnostic |
Field Test Mode (Most Useful)
Dial *3001#12345#* → tap call. Opens hidden Field Test app. Shows: signal strength in dBm (more accurate than bars), connected cellular tower, frequency, Wi-Fi signal in dBm. Closer to 0 = stronger.
Reading: -60 dBm = perfect, -90 dBm = OK, -120 dBm = poor signal.
Show IMEI/Serial
*#06# → instantly displays IMEI (15-digit unique device ID). Useful for: insurance claims, carrier unlocks, theft reports, AppleCare verification. Settings → General → About also shows it but slower.
Call Forwarding Codes
*#21#— see what's currently being forwarded*#62#— forward when phone is unreachable*#61#— forward when no answer*#67#— forward when busy##002#— cancel ALL forwarding
Test Speaker / Mic / Display
Apple removed older diagnostic codes for newer iPhones. Use Apple Diagnostics instead: Settings → General → About → Apple Diagnostics. Or via Apple Support app — guides you through hardware tests.
Voice Quality Test (Old iPhones)
*#92702689# on iPhone 6 and older — opens speaker/mic test. Doesn't work on newer models, removed in iOS 13+.
Check if iPhone is Locked to Carrier
Settings → General → About → 'Carrier Lock' line. 'No SIM Restrictions' = unlocked. Other text = locked. Use this before buying used iPhone.
Battery Cycle Count (iPhone 15+)
Settings → General → About → scroll → Cycle Count. iPhone 15+ shows charge cycle count built-in. Older iPhones: download coconutBattery on Mac, plug iPhone in.
Hidden Force Restart
iPhone 8+: press Vol Up, press Vol Down, hold Side until Apple logo. Use when iPhone hangs. Doesn't lose data — just power-cycles.
Hidden Cell Signal Display
Field Test mode (above) → tap 'Serving Cell Meas' or '2G/3G/LTE Service'. Shows: tower frequency, RSRP, RSRQ, SINR. The dBm reading is more accurate than the bars graphic.
Carriers' Internal Codes (USA)
- Verizon:
#FREE= check minutes - AT&T:
*MIN= minutes left - T-Mobile:
#BAL#= account balance
Mail-In Repair Service
Don't have time to wait for Apple? We offer mail-in repair with overnight return shipping.