Using the tools
You may use the countdowns, alarms, timers and converters for free, for personal or business use.
Alarms and timers depend on your device. A closed tab, a sleeping computer, a muted speaker or a browser that pauses background tabs can stop them from ringing. Do not rely on HowManyHowLong for medication, safety or anything where a missed alert could cause harm.
Accuracy
We work to keep dates and times correct, but we provide the site as is, without warranties. Moon-based holidays such as Eid can move by a day depending on local moon sighting.
Content from others
History and birthday listings come from Wikipedia under the CC BY-SA 4.0 licence. You may reuse that text under the same licence with credit to Wikipedia.
Changes
We may update these terms. The date at the top shows the latest version.