remotion-dev/remotion · error · TypeError

outputRange must contain only numbers, numeric tuples, or su

Error message

outputRange must contain only numbers, numeric tuples, or supported scale, translate, and rotate strings

What it means

Thrown by interpolate() as the final fallback. After the string branch (no strings present) and the tuple branch (not all elements are arrays) are skipped, every remaining output must be a number; if any element is neither a number, a string, nor an array, this TypeError fires. It is the catch-all for outputRange contents the function cannot interpolate.

Source

Thrown at packages/core/src/interpolate.ts:1223

			if (!hasNonNumericString) {
				throw error;
			}

			return interpolateDiscreteString({
				input,
				inputRange,
				outputRange,
				options,
			});
		}
	}

	if (outputRange.every((output) => Array.isArray(output))) {
		return interpolateTuple({input, inputRange, outputRange, options});
	}

	if (!outputRange.every((output) => typeof output === 'number')) {
		throw new TypeError(
			'outputRange must contain only numbers, numeric tuples, or supported scale, translate, and rotate strings',
		);
	}

	checkInfiniteRange('outputRange', outputRange);

	return interpolateNumber({input, inputRange, outputRange, options});
}
/* eslint-enable no-redeclare */

View on GitHub (pinned to 78fe4bb3fd)

Solutions

Ensure outputRange contains only numbers (or only strings, or only tuples).
Map the array to coerce/replace non-numeric values before calling interpolate().
Filter out null/undefined entries so the array is homogeneous.

Example fix

// before
const r = interpolate(t, [0, 1], [0, maybeAngle]); // maybeAngle can be null
// after
const r = interpolate(t, [0, 1], [0, maybeAngle ?? 0]);

Defensive patterns

Strategy: validation

Validate before calling

const allNum = outputRange.every((o) => typeof o === 'number');
const allStr = outputRange.every((o) => typeof o === 'string');
const allArr = outputRange.every((o) => Array.isArray(o));
if (!(allNum || allStr || allArr)) {
  throw new Error('outputRange must be homogeneous');
}
const r = interpolate(input, inputRange, outputRange);

Type guard

const isHomogeneousRange = (x: unknown[]): boolean => {
  const allNum = x.every((o) => typeof o === 'number');
  const allStr = x.every((o) => typeof o === 'string');
  const allArr = x.every((o) => Array.isArray(o));
  return allNum || allStr || allArr;
};

Prevention

Keep outputRange homogeneous: all numbers, all strings, or all tuples.
Filter null/undefined out of the array before the call.
Type the range to a single element kind so mismatches surface at compile time.

When it happens

Trigger: interpolate(0,[0,1],[0, true]); interpolate(0,[0,1],[0, null]); interpolate(0,[0,1],[0, {x:1}]); a mixed array of numbers and booleans/objects.

Common situations: A conditional that injects a boolean into the array; an optional value rendered as null; partial data producing objects instead of numbers.

Related errors

AI-assisted analysis of remotion-dev/remotion@78fe4bb3fd (2026-08-12). Data as JSON: /api/errors/cc984c94021fbabf. Report an issue: GitHub.