Unable to simultaneously satisfy constraints iOS Origin: On your device Last updated 14 Oct 2026

Auto Layout: Unable to simultaneously satisfy constraints. Probably at least one of the constraints in the following list is one you don't want

Two or more Auto Layout constraints conflict; UIKit breaks one to recover and logs this message.

Exact message you may see Unable to simultaneously satisfy constraintsWill attempt to recover by breaking constraintMake a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints
Explore the map of this error Full error map →
Seen on: iOS

Meaning

Common causes: translatesAutoresizingMaskIntoConstraints left true for programmatic views, fixed widths/heights fighting each other, or constraints that don’t fit when a view is collapsed (e.g. height 0 with padding).

Common causes

  • translatesAutoresizingMaskIntoConstraints = true on programmatic views
  • Conflicting fixed width/height constraints
  • Constraints impossible in some states (hidden/zero-size)
  • Duplicate constraints added repeatedly

⚡ Quick fix

  1. Set translatesAutoresizingMaskIntoConstraints = false
  2. Lower priority (999) on the constraint that can give
  3. Use wtfautolayout.com to read the log

Detailed fix by platform

Swift

  1. swift
    view.translatesAutoresizingMaskIntoConstraints = false
let h = view.heightAnchor.constraint(equalToConstant: 44); h.priority = .defaultHigh; h.isActive = true

How to diagnose

  1. Log — Constraint list and which one was broken
  2. Views — Autoresizing constraints (NSAutoresizingMaskLayoutConstraint)?

🔧 Still not fixed?

Many errors look alike. If the steps above didn’t solve it, one of these is probably what you’re facing:

Where this error sits

Origin: On your device. Errors that are often confused with or caused by this one (click to open):

ATS — App Transport Security has blocked a cleartext HTTP resource load (iOS)ATSbuilt for iOS, linking for simulator — Building for iOS Simulator, but linking in object file built for iOS, for architecture arm64 (iOS)built for iOS, linkin…Cannot convert value of type — Swift: Cannot convert value of type 'X' to expected argument type 'Y' (iOS)Cannot convert value …integrity could not be verified — Unable to Install "App": This app cannot be installed because its integrity could not be verified (iOS)integrity could not b…Main Thread Checker — Main Thread Checker: UI API called on a background thread: -[UIView setNeedsLayout] (iOS)Main Thread CheckerNSUnknownKeyException — NSUnknownKeyException: this class is not key value coding-compliant for the key x (iOS)NSUnknownKeyExceptionunable to dequeue a cell with identifier — unable to dequeue a cell with identifier Cell - must register a nib or a class for the identifier or connect a prototype cell in a storyboard (iOS)unable to dequeue a c…Unable to…

Explore the map of this error Full error map →

🧠 Still stuck? Analyze your error

Paste the full message, response headers or stack trace — we'll detect the platform and point to the most likely cause.

💬 What worked for others

No tips yet — did something else fix this for you?

Share what worked for you

Tips are checked by an editor before they appear. Links are removed.