How strong is tremadol?

Tramadol is considered one of the stronger pain killers, but by no means the strongest. Some information you might find useful...
"Tramadol is used in the management of moderate to moderately severe pain. Extended release tablets are used for moderate to moderately severe chronic pain in adults who require continuous treatment for an extended period.
Tramadol is a man-made (synthetic) analgesic (pain reliever). Its exact mechanism of action is unknown, but it is similar to morphine. Like morphine, tramadol binds to receptors in the brain (narcotic or opioid receptors) that are important for transmitting the sensation of pain from throughout the body to the brain. Tramadol, like other narcotics used for the treatment of pain, may be abused. Tramadol is not a nonsteroidal anti-iinflammatory drug (NSAID) and does not have the increased risk of stomach ulceration and internal bleeding that can occur with NSAIDs".

It is for moderate pain. It won't help severe pain.