Starting Strength Calculator
The formula
What the novice line tells you
Rippetoe’s straight line: the same three-session structure where the bar grows 5 kg every squat session, funded by the energy surplus.
Calculation: +5 kg/session × 3/wk; projected vs bodyweight-standard ceiling. Enter your inputs and every substitution is shown below the result.
Reading the result
The program prescribes the slope, not a ceiling — this engine adds the ceiling where the slope stops being legal.
Rules of thumb: Fresh 75 kg male: squat ~40 → 150+ kg within a year on the line
Limitations and best practice
Adding weight to the bar that is really added to the lumbar spine: the +5 kg rule presumes full-depth reps.
This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Frequently asked questions
Do I eat on purpose?
When does it end?
Source & methodology
Rippetoe, Starting Strength 4th ed.
Starting Strength explained: formula, worked example and honest limits
This page was written for one job: turning your own inputs into a defensible figure, with the working shown. Searchers land on a Starting Strength page for three reasons — to plan, to compare options, and to check that somebody else’s arithmetic is honest. This tool serves all three, and everything after the calculator explains the model instead of hiding it.
What makes Starting Strength worth calculating is not precision but position: it tells you which side of a threshold you are on, and by how much. A rough figure that settles the direction beats an elaborate one that never commits.
Individual variation is large here: limb proportions, fibre mix and history all shift how a population-average Starting Strength maps to you. Use it as a starting prescription, then let performance feedback over weeks tune it.
Nothing below is stock text pasted around a number: the worked example computes projected squat = 147.0 kg from this tool’s own defaults, and the sensitivity section ranks the inputs that move the result — Lifter bodyweight first, at ≈10.0 % of the headline for a ten-percent error either way in that input. Work down the page and by the end you could re-derive the result in a spreadsheet from memory.
Every input in Starting Strength, and what it does to the answer
The engine implements a single stated model: +5 kg/session × 3/wk; projected vs bodyweight-standard ceiling. There is no hidden coefficient and no login-gated precision — the formula printed is the formula executed, which is also what makes the result citable.
Squat start (kg) (example value 56) is a measured number in the unit named by the label; the formula does not convert for you. Stay in one unit system top to bottom; conversion rounding is where small errors enter.
Weeks (example value 9) is a measured number in the unit named by the label; the formula does not convert for you. Use the value as of today, not as of the last time you looked — time fields drift silently.
Lifter bodyweight (kg) (example value 98) is a quantity rather than a category — precision here is cheap and worth having. Stay in one unit system top to bottom; conversion rounding is where small errors enter.
The default Starting Strength calculation, written out in full
Abstract formulas are hard to trust, so here is the complete substitution using the default inputs, written the way an examiner would want it. Starting figures: Squat start (kg), Weeks, Lifter bodyweight (kg). The endpoint of that chain is 147.0 kg of projected squat, sitting in the “Linear adds 15 kg a week-pair; from 56 kg the line hits the 1.5× bodyweight practical ceiling (147 kg) in ~6.1 weeks — after that the protocol itself says switch templates” band.
- +5 kg × 3 sessions/wk = +15 kg/wk
- Unbounded line: 56 + 15 × 9 = 191.0
- Ceiling at 1.5 × 98 = 147.0 kg caps it
Raw linear end — 191.0 kg. Read next to the headline, this is the figure that shows the shape of the trade-off.
Gain — 91.0 kg. This is the number experienced users quote when the headline alone would mislead.
Gain per week — 10.1 kg. This is the number experienced users quote when the headline alone would mislead.
Press ceiling warning — press stalls at ~60 % of squat. Compare it against the main result of 147.0 kg before drawing conclusions.
Keep this worked example open while you enter your own figures: matching the shape of the substitution is the fastest way to spot a unit or convention mistake.
How far Starting Strength can reasonably move
The honest version of any estimate is a corridor, and this one is cheap to produce: Starting Strength was recomputed at 5 points along the dominant input, with every other field left untouched.
| Lifter bodyweight setting | Projected squat |
|---|---|
| 80 % of the example value | 117.6 kg |
| 90 % of the example value | 132.3 kg |
| example inputs | 147.0 kg |
| 110 % of the example value | 161.7 kg |
| 120 % of the example value | 176.4 kg |
The corridor runs from 117.6 kg to 176.4 kg across that band — which is the range worth planning inside rather than the single 147.0 kg point estimate. Reproduce it in the form above by editing Lifter bodyweight alone; the substitution steps will follow your figures exactly.
Sensitivity: which inputs change Starting Strength the most
This list was computed for this specific engine just now: each numeric input was nudged ±10 % while every other field held its example value, and the projected squat was recalculated from scratch. It is the fastest honest answer to “what matters most in Starting Strength?” — and it is specific to these defaults, because sensitivity moves with the starting point.
- Nudge Lifter bodyweight by ±10 % and Starting Strength lands between 132.3 kg and 161.7 kg (sensitivity ≈10.0 %)
Lifter bodyweight is the dominant lever here: ten percent either way moves the result by about 10.0 %, from 132.3 kg to 161.7 kg. Measure that input from a document rather than from memory. Everything below that can stay approximate, which is a licence to stop chasing data that would not change the decision.
Is your Starting Strength good — reading the result bands
A number on its own is trivia; a number against a range is intelligence. The default case lands in the “Linear adds 15 kg a week-pair; from 56 kg the line hits the 1.5× bodyweight practical ceiling (147 kg) in ~6.1 weeks — after that the protocol itself says switch templates” band, and bands are deliberately wide because real situations overlap. Before treating the band as fact, note its width: ten percent either way on Lifter bodyweight already spans 132.3 kg to 161.7 kg. The practical reading rules: read the band as a starting hypothesis, then test it: change the two dominant inputs by ten percent and see whether the verdict survives. Verdicts that survive stress are the ones worth acting on.
In Fitness & Sports, Starting Strength is one instrument in an orchestra: on its own it is a number, next to Raw linear end and Gain it becomes a diagnosis. The tools linked above exist so the headline never has to carry that weight alone.
Why Starting Strength results go wrong — and how to prevent it
Adding weight to the bar that is really added to the lumbar spine: the +5 kg rule presumes full-depth reps. This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Stopping at the first plausible answer. If the result surprises you, the productive question is which input would have to be wrong for the surprise to disappear — then go check that input.
Attention is also misallocated between fields. Having measured this engine, we can say where it belongs: Lifter bodyweight first, everything else second.
The subtlest error is answering the wrong question precisely. Confirm that projected squat is actually the quantity your decision needs — the arithmetic is flawless either way, which is what makes the mistake invisible.
Before you trust your Starting Strength: a short checklist
- Check that every field the formula needs actually arrived from a document, not from recollection.
- Compare the result with one independent method or published benchmark.
- Re-verify Lifter bodyweight against a source document — ten percent of error there moves the headline by ≈10.0 %.
- Record the date and the inputs alongside the number so future-you knows what was assumed.
- Compare the output against one published benchmark or a colleague’s independent estimate.
- Run the ±10 % stress on the top two levers and check that your conclusion survives both.
A routine for decision-grade Starting Strength
Using a calculator well sounds trivial, but the difference between a decision-grade figure and a throwaway one lives entirely in the routine. The routine for Starting Strength takes a minute to learn and applies to every input above.
Step 1 — start from evidence. The inputs behind Starting Strength are squat start (kg), weeks, lifter bodyweight (kg). Write them down with their source next to each one; if you cannot name where a figure came from, that is the input most likely to be wrong. When in doubt, prefer the boring input: the interesting one is usually the one you misread.
Step 2 — start from the case you can defend. Enter pessimistic-but-honest figures first; the optimistic run is a ceiling, not a plan. A conclusion that holds on conservative inputs holds everywhere. Comparisons are cheap: run the identical calculation for the alternative and look at the gap.
Step 3 — play with the inputs on purpose. Ten percent up, ten percent down, one field at a time. Within a few minutes you will know this calculation better than most people who quote its results. Say the answer out loud before you save it; if it sounds wrong, the model did not change, your understanding did.
Step 4 — run the scenario trio. Expected, pessimistic, optimistic. The gap between pessimistic and expected is the number to plan against; the optimistic result is useful only as a ceiling. The point of transparency is that a reader can disagree with a specific line rather than with you.
Step 5 — write the one-line memo. “Projected squat = 147.0 kg on this date, from these inputs.” That line is the entire deliverable; everything else on this page is how you earned the right to write it. Say the answer out loud before you save it; if it sounds wrong, the model did not change, your understanding did.
Where Starting Strength matters in practice
Numbers earn their keep in conversations, and Starting Strength is no exception. In Fitness & Sports discussions around Strength Training, this figure decides whether an option stays on the table: it converts an opinionated debate into an arithmetic one, and arithmetic is the only referee both sides accept. When two sources disagree, it is almost never the arithmetic that differs.
The audience for this page is people who need one trustworthy number before their next decision. In professional Strength Training practice the pattern is always the same — screen with Starting Strength, then invest slow analysis only in whatever survives the screen. A calculation you cannot explain to somebody else is a calculation you cannot defend.
Nothing here is stored or transmitted, so the habit of checking is free: open the page, re-enter current figures, compare with the number you saved last time. Precision is a promise you make about your data; make sure your inputs can keep it.
Quick answers: what searchers ask about Starting Strength
What affects Starting Strength the most?
Measured on this engine, Lifter bodyweight is the dominant lever: moving it ±10 % shifts the projected squat across 132.3 kg to 161.7 kg — about 10.0 % of the headline. The ranked list in the sensitivity section is computed live, not asserted from a template.
What is a typical Starting Strength?
On the worked example above Starting Strength comes out at 147.0 kg. Treat that as one point on a distribution rather than a norm: the bands, the companion outputs and the sensitivity ranking tell you how wide the plausible range really is.
How do I calculate Starting Strength by hand?
+5 kg/session × 3/wk; projected vs bodyweight-standard ceiling is the entire method. Work the inputs in that order — +5 kg × 3 sessions/wk = +15 kg/wk — and you will reach 147.0 kg on the default figures, the same number this tool prints.
What happens to Starting Strength if lifter bodyweight changes by 10 %?
On these inputs a ±10 % change in lifter bodyweight takes Starting Strength to 161.7 kg against the 147.0 kg example — around 10.0 % of the headline. The same test on every other field is in the sensitivity section.
Is the Starting Strength result of 147.0 kg good or bad?
Good and bad are comparisons, so the honest test is three questions: where does your own Starting Strength sit against the 147.0 kg reference above, how far would a plausible input error move it (≈10.0 % per ten percent on Lifter bodyweight), and what does the alternative option compute to?
What affects Starting Strength the most?
Sensitivity depends on where you start, but the inputs Squat start (kg) and Weeks typically move Starting Strength further than the rest because they enter the formula multiplicatively. If you can only measure two things well, measure those and hold the others at conservative defaults.
Is Starting Strength accurate?
The arithmetic is exact: +5 kg/session × 3/wk; projected vs bodyweight-standard ceiling is evaluated with full floating-point precision and every substitution is printed in the worked example. What limits accuracy is input quality and the model’s assumptions, so treat the 147.0 kg result as the correct answer to the question you typed — and check the assumptions section before acting on it.
Do I eat on purpose?
Yes — novice gains stall instantly in a deficit; the protocol assumes 0.25–0.5 % bodyweight gain per week.
When does it end?
When a prescribed +5 fails twice; then Intermediate Novice splits the slope.
Is my data private on this page?
Yes — computation happens locally in your browser, with no account, no tracking of your inputs and nothing sent to a server. The printed formula is the whole story of what happens to your figures.
What the labels on this page mean
- Raw linear end
- 191.0 kg in the default Starting Strength calculation — one of the secondary figures an experienced reader checks before trusting the primary number.
- Gain
- 91.0 kg for the Starting Strength worked case; it sits next to the main result because it carries context the headline leaves out.
- Gain per week
- 10.1 kg for the Starting Strength worked case; it sits next to the main result because it carries context the headline leaves out.
- Projected squat
- The primary output of this tool: 147.0 kg for the default inputs, computed exactly from +5 kg/session × 3/wk; projected vs bodyweight-standard ceiling.
- Worked example
- The calculation written out in full so that nothing on this page has to be taken on trust.
- Verdict band
- The interpretation attached to a result (“Linear adds 15 kg a week-pair; from 56 kg the line hits the 1.5× bodyweight practical ceiling (147 kg) in ~6.1 weeks — after that the protocol itself says switch templates” on these inputs), which turns a bare number into a position on a scale.
- Sensitivity (±10 %)
- How far the Starting Strength moves when a single input is nudged ten percent either way; the ranked list on this page is computed live from this engine.
Method, sources and what this tool cannot tell you
The model is published arithmetic implemented exactly as written: +5 kg/session × 3/wk; projected vs bodyweight-standard ceiling. Source of record: Rippetoe, Starting Strength 4th ed. Where a professional version of this calculation differs, it differs in inputs and jurisdiction-specific coefficients, not in the algebra — which is why re-checking your inputs beats hunting for a second calculator.
Nothing here replaces a qualified professional, and nothing here is approximate either — the arithmetic is exact, and the honesty is in the inputs you supply. The design constraint was set by usefulness rather than by comfort: an estimate you can interrogate beats an answer you have to trust.
What to do with your Starting Strength next
Save the number together with its inputs and today’s date; a Starting Strength figure without context is unusable the moment an input changes.
This page was written for people who need one trustworthy number before their next decision, and the promise is that nothing above required trust. Bookmark the tool, re-run it whenever an input moves by more than a few percent, and keep the date with the number.