How to Fix Rangeerror in NestJS

A rangeerror in NestJS typically signals a straightforward problem with a clear solution. Understanding why it occurs is the first step toward a permanent fix.

What Causes RangeError

A RangeError in NestJS occurs when a value falls outside its permitted range. Common triggers include:

• Array or string index out of bounds
• Invalid arguments to built-in functions (negative array sizes, invalid string indices)
• Infinite recursion exceeding the maximum call stack size
• Numeric overflow or underflow in calculations
• Pagination parameters pointing past the end of a collection

How to Fix It

// Validate pagination parameters at the API boundary
function paginate<T>(items: T[], page: number, size: number): T[] {
  if (!Number.isFinite(page) || page < 1) {
    throw new RangeError(`Page must be >= 1, got ${page}`);
  }
  if (!Number.isFinite(size) || size < 1 || size > 100) {
    throw new RangeError(`Size must be 1-100, got ${size}`);
  }
  const start = (page - 1) * size;
  if (start >= items.length) return [];
  return items.slice(start, start + size);
}

// Usage with NestJS
@Get("users")
getUsers(@Query("page") page = 1, @Query("size") size = 20) {
  return paginate(this.users, Number(page), Number(size));
}

Validate pagination parameters with Number.isFinite() checks and return empty results instead of throwing for out-of-range pages.

Prevention Strategies

• Validate all numeric inputs at API boundaries before they reach internal logic
• Add depth limits to recursive algorithms as a safety net
• Use safe accessor methods that return null/None/Option instead of throwing
• Add upper bounds to user-supplied size parameters to prevent resource exhaustion

Catch RangeErrors before they hit production with [Bugsly](https://bugsly.dev) — get full stack traces and the exact value that was out of range for every error in your NestJS app.