Two kinds of damages, one of which has no invoice
A personal injury claim is built from two kinds of loss. Economic damages, called specials, are the ones with paper behind them: medical bills, the cost of future treatment, wages lost while unable to work, mileage to appointments, prescriptions, household help. You add them up and the total is what it is.
Non-economic damages, called generals, are the pain itself, the loss of enjoyment of ordinary life, the disfigurement, the anxiety, the inability to lift a child or sleep through the night. They are real losses that the law compensates, and nobody issues a receipt for them.
That gap is why the two conventions on this page exist. The multiplier method takes the documented specials as a proxy for how bad the injury was and multiplies them. The per-diem method assigns a daily value to living with the injury and multiplies it by the days of recovery. Neither is a rule of law. Both are ways of turning an argument into a number that two parties can move toward each other on.
Understanding that they are conventions matters practically. An adjuster's software runs something similar; a judge instructs a jury to award what is fair from the evidence, with no reference to any multiple. So the output of this page is a negotiating position, and its usefulness is that it is explicit about which assumption produced which number.
How each method works, and what drives it
The multiplier method. Total the specials, then multiply by a factor. The factor is meant to scale with severity: the low end for a soft-tissue injury with complete recovery and no lasting effect, the high end for permanent impairment, disfigurement, surgery, or an injury that changes what the claimant can do for the rest of their life. Practitioners commonly argue in the 1.5 to 5 range, and this calculator defaults to 1.5 and 3 because a range is the honest output. These are negotiating conventions rather than published statistics — no data set assigns a specific multiplier to a specific diagnosis, and anyone quoting one as though it were measured is quoting a convention.
The method's weakness is structural: it makes general damages proportional to the medical bills. That gives a perverse result in two directions. A claimant who is stoic, or well-insured, or who lives where care is cheap, accrues fewer bills for the same injury and is valued lower. A claimant who receives extensive but low-value treatment accrues more bills and is valued higher. Defence counsel argue the first point; adjusters watch for the second, which is why treatment that looks inflated is scrutinised rather than simply multiplied.
The per-diem method. Choose a defensible daily rate and multiply by the days from injury to maximum medical improvement. The strongest anchor for the rate is the claimant's own daily earnings — the argument being that enduring a day of pain is worth at least what a day of work is worth. That anchoring is what makes the number defensible; a rate pulled from nowhere is a number an adjuster will simply discount.
Its weakness is the opposite of the multiplier's: it works well for a defined recovery period and breaks down entirely for a permanent injury, where the days do not stop. Nobody argues a per diem over a 40-year life expectancy, because the product is absurd. For permanent injuries, practitioners fall back on the multiplier or on comparable verdicts.
Translating between them. Any per-diem figure implies a multiplier — divide it by the specials — and any multiplier implies a number of days at a given rate. This calculator shows both translations, and the cross-check is useful: if the per-diem figure implies a 7× multiplier, or the multiplier implies a recovery period twice as long as the records support, one of the two inputs is not defensible.
Comparative fault reduces whatever total you arrive at. If the claimant is 25% responsible, the recovery is 75% of the figure. The rules vary sharply by state: pure comparative negligence reduces at any percentage, modified comparative negligence bars recovery entirely once the claimant reaches 50% or 51% depending on the state, and a small number of contributory-negligence jurisdictions bar recovery for any fault at all.
Worked example: a rear-end collision with a four-month recovery
A claimant is rear-ended at a stop light. Emergency department, imaging and fourteen sessions of physical therapy come to $12,000. The treating physician expects a further $3,000 of care. The claimant misses three weeks of work at $1,833 a week, so $5,500, and has $800 in prescriptions, mileage and a lumbar support. Recovery to maximum medical improvement takes 120 days. Liability is admitted.
- Economic damages. 12,000 + 3,000 + 5,500 + 800 = $21,300.
- General damages at 1.5×. 21,300 × 1.5 = $31,950.
- General damages at 3×. 21,300 × 3 = $63,900.
- Claim range. 21,300 + 31,950 = $53,250 at the low end; 21,300 + 63,900 = $85,200 at the high end.
- Midpoint. At the average multiplier of 2.25, generals are 21,300 × 2.25 = $47,925 and the claim is $69,225.
- Per-diem cross-check. The claimant earns about $1,833 a week, which is 1,833 ÷ 7 = $262 a calendar day; using a conservative $200 a day over 120 days gives $24,000 of general damages, and a total of $45,300.
- What the cross-check tells you. $24,000 ÷ $21,300 = an implied multiplier of just 1.13×, below even the low end of the range being argued. To reach the $47,925 midpoint at $200 a day would take 47,925 ÷ 200 = 240 days, twice the documented recovery. So on these facts the per-diem method produces the weaker demand, and the multiplier method is the one to lead with.
- If fault were shared. At 25% claimant fault, the $69,225 midpoint becomes 69,225 × 0.75 = $51,919.
Notice how much of the answer is assumption. The documented specials are $21,300 and everything else — a range of $53,250 to $85,200, or $45,300 on the per-diem basis — turns on two numbers nobody can document. That is the honest state of a pre-litigation valuation, and presenting it as a range makes the assumption visible instead of hiding it inside a single figure.
How to use the range without over-trusting it
Lead with the specials, because they are the part you can prove. A demand package that documents every bill, every day off work and every receipt puts the only defensible number on the table first. The generals argument then rests on that foundation rather than floating free.
The multiplier is argued, not calculated. What moves it is evidence: objective findings on imaging rather than subjective complaints, a surgery rather than conservative care, a permanent impairment rating, visible scarring, a documented inability to return to a specific activity. Records that show a gap in treatment, or a rapid return to full function, move it the other way.
Both methods ignore everything that actually decides a case. Venue matters — juries in different counties value the same injury very differently. The policy limits matter, and frequently cap the outcome regardless of the calculation. Liability strength matters: a disputed-liability case with a strong damages story may settle below a clear-liability case with modest injuries. Comparable verdicts and settlements in the same venue are better evidence of value than any multiple.
Check what the claimant actually keeps. A gross settlement figure is not what reaches the claimant. Attorney fees, case costs, medical liens, health insurer subrogation and statutory Medicare or Medicaid recovery all come out first, and a settlement heavy on medical specials can leave a surprisingly small net after liens are resolved.
Watch the statutory limits. Many states cap non-economic damages in medical malpractice and some cap them more broadly; damages against public entities are frequently capped and subject to short notice periods. A calculated figure above the applicable cap is not a claim value.
Claim value across the multiplier range, on $20,000 of specials
| Multiplier | General damages | Total claim | Days at $200/day to match | Daily rate over 180 days to match |
|---|---|---|---|---|
| 1.0× | $20,000 | $40,000 | 100 | $111.11 |
| 1.5× | $30,000 | $50,000 | 150 | $166.67 |
| 2.0× | $40,000 | $60,000 | 200 | $222.22 |
| 2.5× | $50,000 | $70,000 | 250 | $277.78 |
| 3.0× | $60,000 | $80,000 | 300 | $333.33 |
| 4.0× | $80,000 | $100,000 | 400 | $444.44 |
| 5.0× | $100,000 | $120,000 | 500 | $555.56 |
Reading across a row is the fastest consistency check available: a 3× demand on these specials is the same as claiming 300 days at $200 a day, so the treatment records had better support a recovery of roughly that length.
This is not a valuation and not legal advice
No formula determines the value of a personal injury claim. The multiplier and per-diem methods are negotiating conventions; courts do not apply them, and a jury is instructed to award what it finds reasonable on the evidence before it. Outcomes turn on venue, liability strength, the credibility of the claimant and the treating providers, insurance policy limits, statutory caps on non-economic damages, and the applicable comparative or contributory negligence rule — none of which appear in this arithmetic. Statutes of limitation and notice requirements run from the date of injury and are short in claims against public entities. Consult an attorney licensed in the relevant jurisdiction before relying on any number for a decision.
Errors that produce an indefensible number
- Including undocumented losses in the specials. Everything in the economic column should have a bill, a pay record or a receipt behind it, because the whole demand is anchored to that total.
- Double-counting lost wages. Wages lost during the recovery period are economic damages; the per-diem rate is compensation for the pain of those same days. Anchoring the daily rate to earnings is standard, but do not then also claim the earnings twice.
- Applying a per diem to a permanent injury. The days do not stop, and multiplying a daily rate by a life expectancy produces a figure nobody will engage with.
- Quoting a multiplier as though it were data. There is no published table mapping diagnoses to multipliers. Presenting a convention as a measured statistic invites a challenge you cannot answer.
- Ignoring liens and subrogation. A gross figure that looks adequate can leave very little net once health insurer, hospital and statutory liens are satisfied.
- Forgetting the comparative negligence rule in the forum. The same 51% finding reduces recovery in one state and eliminates it in the next.
- Applying the multiplier to inflated treatment. Because generals are proportional to specials, treatment that looks disproportionate to the injury increases the calculated value while decreasing the claim's credibility.
- Presenting a single number. A range, with the assumption behind each end stated, is more persuasive than a point estimate whose derivation is hidden.
Where these methods sit in valuing a claim
Damages valuation runs on a ladder of evidence. At the bottom is the arithmetic on this page — quick, transparent, and entirely assumption-driven. Above it sit comparable verdicts and settlements from the same venue for similar injuries, which is what experienced counsel actually rely on. Above that, in cases of size, sit expert evidence: a life-care plan for future medical needs, a vocational assessment and an economist's report for lost earning capacity, and a functional capacity evaluation for what the claimant can still do.
The economic side has its own arithmetic. Future medical costs and future lost earnings are streams over time, so a defensible figure discounts them to present value rather than simply adding the years together — the same reasoning as a net present value calculation, and the discount rate is frequently contested. Lost earnings for a self-employed claimant have to be reconstructed from business records rather than pay stubs, which is close to the exercise in a freelance hourly rate calculation.
Where a vehicle is involved, the property side of the claim runs in parallel and is valued by its own conventions, including the 17c diminished value formula. And on the firm's own side of the ledger, the economics of taking a contingency case at all depend on case hours against recovery, which is the ground a billable utilisation calculation covers.
Key terms
- Special damages
- Economic losses with a documented value: medical bills, future treatment costs, lost wages, out-of-pocket expenses. Sometimes just called specials.
- General damages
- Non-economic losses — pain, suffering, loss of enjoyment of life, disfigurement, emotional distress. Compensable but not itemisable.
- Multiplier method
- Estimating general damages as a multiple of the economic damages, conventionally between about 1.5 and 5 depending on severity.
- Per-diem method
- Estimating general damages as a daily rate times the number of days from injury to maximum medical improvement.
- Maximum medical improvement
- The point at which the claimant's condition has stabilised and further treatment will not materially improve it. It ends the per-diem period.
- Comparative negligence
- A rule reducing recovery by the claimant's share of fault. Pure comparative reduces at any percentage; modified comparative bars recovery at 50% or 51%.
- Subrogation and liens
- The right of a health insurer, hospital or government programme to be repaid out of the settlement. They come out of the gross figure before the claimant is paid.