LTIFR calculator and TRIFR calculator
This LTIFR calculator gives your lost time injury frequency rate and your total recordable injury frequency rate (TRIFR), both per one million hours worked. Enter the hours worked and the injuries in the same period. The answer shows the formula, so you can check it.
2. Injuries in the same period (count each injury once, in its most serious group)
LTIFR
-
Enter the hours worked.
TRIFR
-
Enter the hours worked.
Both rates are per 1,000,000 hours worked. Nothing you type leaves your browser.
LTIFR formula and TRIFR calculation
LTIFR = lost time injuries × 1,000,000 ÷ hours worked
TRIFR = recordable injuries × 1,000,000 ÷ hours worked
Recordable injuries are the lost time injuries plus the medical treatment, restricted duty and other recordable injuries, such as a loss of consciousness. Count each injury once, in its most serious group.
Worked example
A builder's crews worked 450,000 hours in the last 12 months. There were 3 lost time injuries, 5 medical treatment injuries and 2 restricted duty injuries.
- LTIFR = 3 × 1,000,000 ÷ 450,000 = 6.67
- TRIFR = (3 + 5 + 2) × 1,000,000 ÷ 450,000 = 22.22
Safe Work Australia uses the same per million hours maths in its own example: 100 claims over 20.0 million hours is a rate of 5.00.
TRIFR calculator: what counts as a recordable injury
The TRIFR calculator above adds four groups into one recordable total. SafeWork NSW describes a recordable injury as any event that causes impairment to a worker, whether that is a loss of consciousness, medical treatment, restricted duties or lost time. A worker who sees a doctor for stitches and comes straight back is a medical treatment injury. A worker who returns on light duties is a restricted duty injury. A worker who misses one full day or shift or more is a lost time injury.
Use the same period for injuries and hours, often 12 months or a rolling 12 months. Safe Work Australia suggests small businesses use a longer period, such as 5 years, because one injury swings the rate a lot when hours are low. Keep the injury register and the hours records that sit behind each rate, so anyone can check the numbers.
LTIFR quick reference table
The rate for a given number of lost time injuries at different hours worked. The same table works for TRIFR if you read the left column as recordable injuries.
| Injuries | 100,000 hrs | 250,000 hrs | 500,000 hrs | 1,000,000 hrs | 2,000,000 hrs |
|---|---|---|---|---|---|
| 1 | 10.00 | 4.00 | 2.00 | 1.00 | 0.50 |
| 2 | 20.00 | 8.00 | 4.00 | 2.00 | 1.00 |
| 5 | 50.00 | 20.00 | 10.00 | 5.00 | 2.50 |
| 10 | 100.00 | 40.00 | 20.00 | 10.00 | 5.00 |
A small crew works far fewer hours, so one injury moves the rate a lot. 25 workers on 38 hours a week for 48 weeks is about 45,600 hours, where one lost time injury is an LTIFR of 21.93.
How it works
A frequency rate turns a count of injuries into a rate you can compare between periods and between businesses of different sizes. Dividing by hours worked takes out the size, and multiplying by one million gives a number that is easy to read. The calculator adds your injury groups to get the recordable total, then runs both formulas. If you do not have an hours figure, the estimate multiplies workers by weekly hours by weeks worked.
Safe Work Australia now publishes its national figures as workers' compensation injury frequency rates, which count accepted claims rather than every injury, and it treats one day or shift of time lost as 3 hours. Your own LTIFR counts your own injuries, so it will not match the national figure exactly. Both agencies warn against using one injury rate as the only measure of how safe a business is.
Common questions
▸What is LTIFR?
LTIFR is the lost time injury frequency rate: the number of lost time injuries for every one million hours worked. Safe Work Australia counts a lost time claim when a worker has one day or shift or more off work, or the injury is a fatality or a permanent impairment.
▸What is TRIFR?
TRIFR is the total recordable injury frequency rate: all recordable injuries for every one million hours worked. SafeWork NSW describes a recordable injury as any event that causes impairment to a worker, whether a loss of consciousness, medical treatment, restricted duties or lost time.
▸How do you calculate LTIFR?
Multiply the number of lost time injuries by 1,000,000, then divide by the total hours worked in the same period. For example, 3 lost time injuries in 450,000 hours gives 3 × 1,000,000 ÷ 450,000 = 6.67.
▸What is the difference between LTIFR and TRIFR?
LTIFR counts only injuries that cost time off work. TRIFR counts every recordable injury, including medical treatment and restricted duty injuries with no time lost. TRIFR is always equal to or higher than LTIFR for the same period.
▸What is a good LTIFR?
Lower is better, but there is no official pass mark, and a low LTIFR does not prove a site is safe. SafeWork NSW calls lost time measures productivity indicators, not valid measures of harm to people, and Safe Work Australia says injury rates should not be the only measure of WHS performance. Compare against your own past years, and use the rates alongside inspections, near misses and how well controls are working.
▸How do you calculate TRIFR?
Add up all recordable injuries in the period (lost time, medical treatment, restricted duty and other recordable injuries), multiply by 1,000,000, then divide by the hours worked in the same period. For example, 10 recordable injuries in 450,000 hours gives a TRIFR of 22.22.
Sources
Lower the rate at the source
The rate only tells you what already happened. A site-specific SWMS sets the controls for the high risk work where most serious injuries start. Log every injury on the incident report form and check whether it must be reported with the notifiable incident checker.
Build a SWMS for A$39More free tools
✅ Do I need a SWMS?
Pick your state and job, find out if a SWMS is legally required.
🛡️ SWMS compliance self-check
Score your SWMS against what a principal contractor checks before you send it.
💰 SWMS cost calculator
Compare the true cost of a SWMS: your own time, a consultant, or a generator.
📋 JSA builder
Build a printable Job Safety Analysis: steps, hazards, risk ratings, controls.
🔢 Risk matrix calculator
Score a hazard on the 5×5 matrix: likelihood × consequence.
🪪 High risk work licence checker
Find out which high risk work licence a task needs.
🚧 Site induction checklist
Generate a printable site induction checklist for new workers.
📝 Incident report form
Generate a printable incident and injury report form for your site.
🚨 Is this incident notifiable?
Check if a workplace incident must be reported to the regulator, and who to tell.
🖊️ Toolbox talk sign-on sheet
Printable attendance sheet so your toolbox talk is documented.
✋ Take 5 card
Fill in a Take 5 before the task, then print it or save it as a PDF.
🧯 Fire extinguisher types selector
Pick the fire class or hazard, see which extinguisher types suit it and their colour band.
Guides
What is a SWMS?How to write a SWMSHierarchy of controlsThe 18 HRCW categoriesAll guides
Need the real document, not just a tool?
A site-specific SWMS for your trade, verified and delivered in minutes. A$39, or A$179 for every SWMS your trade needs.
Build my SWMS for A$39