2026-09-15 8 min

Vitamin K Intake Calculator

Free vitamin K intake calculator that totals vitamin K from foods and supplements, compares it against the sex-specific adequate intake (120 mcg men, 90 mcg women), and returns coverage, a 0–100 score, and steadiness guidance for blood-thinner users.

Calculator

Gender

Age

yrs

Full years

Food vitamin K

mcg

Kale, spinach, collards, broccoli, natto, soybean oil

Supplement vitamin K

mcg

All pills, powders, drops combined

Results update live as you type

Status:100 mcg total83.3% of AIBelow target — 88/100

Results

Total daily intake100 mcg

% of daily target83.3%

Intake score88/100

Daily target (AI)120 mcg

Illustrative ceiling (2× target)41.7% of limit

Gap to target20 mcg short

Food plus supplements vs AI target

Intake Breakdown

Component	Amount	% of target
Food intake	100 mcg	83.3%
Supplements	0 mcg	0%
Total intake	100 mcg	83.3%
Daily target (AI)	120 mcg	100%
Gap to target	20 mcg	16.7%
Illustrative ceiling (2× target)	240 mcg	41.7%

Recommendations

▸Add about 20 mcg daily from kale, spinach, or broccoli to close the gap to target
▸Eat cooked greens 3–4x weekly — one cup of kale covers several days.
▸Eat K with some fat; gut bacteria also manufacture a share.
▸Re-run after 2–4 weeks of consistent eating or any supplement change

Results

Normal

Total daily intake

100 mcg

Food plus supplements vs AI target

% of daily target

83.3%

Share of the 120 mcg AI

Intake score

88/100

Proximity to target with upper-limit penalty

Daily target (AI)

120 mcg

120 mcg men / 90 mcg women adequate intake

Illustrative ceiling (2× target)

41.7% of limit

No upper limit is set for vitamin K — the bar shows twice the target as a commonsense reference.

Gap to target

20 mcg short

What remains to reach the daily target

Age- and sex-specific DRI targets with an upper-limit safety check. Self-reported intake runs 10–20% error — average 3–7 days for a stable reading.

Visualizations

Intake vs target (mcg)

120Target

100Total

240Illustrative ceiling (2× target)

Where intake comes from

Food83%

Supplements0%

Gap to target17%

Coverage of daily target

83.3%

0200

Formula

Vitamin K coverage prices total micrograms against the sex-specific adequate intake with steadiness emphasis.

Coverage = total intake / AI target x 100

Alternative Form

Total = food + supplements; Gap = target − total

Variables

Symbol	Name	Unit	Description
Total	Total intake	mcg/day	Food plus supplement vitamin K per day
Target	Daily target	mcg/day	AI value for the selected age and sex
Coverage	Coverage	%	Total as a share of target
Gap	Gap to target	mcg	Shortfall remaining when coverage is under 100%
Limit	Upper boundary	mcg/day	No upper limit is set for vitamin K — the bar shows twice the target as a commonsense reference.
Score	Intake score	0-100	Proximity to target with an over-limit penalty

Explanation

Coverage rewards landing near 100% of target; the score falls as intake drifts low or high, and collapses when the upper limit is breached.

Derivation

Target from DRI tables by age and sex. Coverage = total / target x 100. Score = 100 − |coverage − 100| x 0.7, capped at 35 above the upper limit, floored at 5.

Step-by-Step Calculation

Follow each step to understand how the result is calculated from your inputs.

Step 1

Add food and supplement sources into one daily total.

Total = food + supplements

Food:100 mcg

Supplements:0 mcg

Intermediate: Same-unit daily sum

Result: Total 100 mcg

Step 2

Look up the AI daily target for the selected age and sex.

AI by age and sex

Target:120 mcg

Intermediate: 120 mcg men / 90 mcg women adequate intake

Result: Target 120 mcg

Step 3

Express intake as a share of target.

Coverage = total / target x 100

Coverage:83.3%

Intermediate: 100 / 120 x 100

Result: 83.3% of daily target

Step 4

Measure the remaining gap, if any.

Gap = target − total

Gap:20 mcg short

Intermediate: 120 − 100

Result: Add 20 mcg from food first

Step 5

Check the total against the upper safety boundary.

Upper-limit share = total / limit x 100

Boundary:240 mcg

Share:41.7%

Intermediate: No upper limit is set for vitamin K — the bar shows twice the target as a commonsense reference.

Result: Inside the safe boundary

Step 6

Convert coverage and safety into one score and act on it.

Score = 100 − |coverage − 100| x 0.7 (capped at 35 over limit)

Score:88/100

Status:Below target

Intermediate: Add about 20 mcg daily from kale, spinach, or broccoli to close the gap to target

Result: Add about 20 mcg daily from kale, spinach, or broccoli to close the gap to target

Final Answer

100 mcg

Worked Examples

See how the calculator works with different scenarios.

Scenario

A 30-year-old man getting 47.2 mcg of vitamin K from food and none from supplements.

Inputs

Food:47.2 mcg

Supplements:0 mcg

Calculation

Total = 47.2 mcg. Coverage = 47.2 / 120 x 100 = 45%.

Result

~45%% of target — Low status

Interpretation

Classic gap: no greens for weeks plus a long antibiotic course.

Understanding Your Result

Your Result: Total daily intake: 100 mcg

Typical range: AI 120 mcg men / 90 mcg women; no UL; one cup cooked kale holds ~500 mcg.

What This Means

Compare daily vitamin K against the 120/90 mcg adequate intake, with clotting-aware guidance. Coverage of the daily target, a safety check, and a 0–100 intake score.

Why It Matters

Greens decide this score in a single serving — coverage math ends the guessing.

Professional Interpretation

Counsel like a dietitian: preach greens steadiness, especially around warfarin — swings, not salads, cause harm.

K1 vs K2

Leafy K1 covers clotting needs; fermented-food K2 is a bonus researchers still study.

Total beats any single source

The body counts food plus supplements together — log both before judging coverage.

Recommendations

•Eat cooked greens 3–4x weekly
•Keep vitamin K steady if on warfarin — coordinate changes
•Prefer food sources before raising supplement doses
•Re-check after 2–4 weeks of consistent intake
•Pair this check with the Daily Micronutrient Calculator for the full picture

Educational Content

Introduction

Concept Explanation

Total daily vitamin K from foods plus supplements, priced against the sex-specific adequate intake.

Applications

▸Auditing clotting-and-bone vitamin K coverage

▸Checking whether supplements are still needed

▸Comparing food-first vs supplement strategies

▸Adjusting intake for age and sex differences

▸Spotting excess before it becomes a habit

▸Planning meals around the richest food sources

Benefits

•One headline coverage number with a 0–100 score
•Food vs supplement split at a glance
•Upper-limit safety check built in
•Age- and sex-specific targets automatically
•Concrete food fixes for any gap

Limitations

•Self-reported intake averages 10–20% error
•Absorption varies with gut health and pairings
•Single-day snapshot; needs shift with diet phases
•Clinical deficiency needs lab tests, not estimates

Best Practices

•Log 3–7 typical days, not one perfect day
•Rotate kale, spinach, and broccoli
•Count fortified foods under food, not supplements
•Re-run when diet, age band, or supplements change
•Confirm persistent lows or highs with a clinician

Common Misconceptions

Myth: Vitamin K is dangerous with blood thinners.

Truth: Keep K steady rather than zero — sudden swings, not salads, destabilize warfarin. Coordinate with your clinician.

Myth: If some is good, more is always better.

Truth: Coverage plateaus at 100% — beyond the target only the upper limit matters.

Myth: Supplements beat food for every nutrient.

Truth: Foods bundle fiber, co-factors, and slower release that pills rarely match.

Practical Tips

•Batch-cook one greens side weekly
•Photograph meals for 3 days to calibrate portions
•Read supplement labels for elemental amounts, not compound weight
•Spread doses that absorb better in smaller amounts
•Recheck this calculator monthly while adjusting
•Keep one steady breakfast to anchor daily intake

Common Mistakes

Counting one perfect day as typical

Average 3–7 ordinary days including weekends and eating out.

Logging compound weight instead of elemental dose

Use the elemental vitamin K line on the Supplement Facts panel.

Forgetting fortified foods and drinks

Count fortified cereals, milks, and energy drinks under food intake.

Stacking overlapping supplements

Add every pill, powder, and gummy into one supplement total before judging.

Chasing 100% every single day

Weekly averages decide status — land in the 90–120% band most days.

Assumptions

This calculator makes the following assumptions to provide estimates:

DRI targets: AI values from the Institute of Medicine DRI tables for adults.

Additive sources: Food and supplement amounts add directly into one daily total.

Steady state: Inputs represent a typical day, not a single unusual spike.

Adult ranges: Targets assume non-pregnant, non-lactating adults unless noted.

Limitations

Be aware of these limitations when using this calculator:

Estimate, not diagnosis: Coverage math cannot diagnose deficiency or toxicity.

Absorption ignored: Pairings, gut health, and medication effects are not modeled.

Label error: Food database and label values vary 10–20% from actual content.

Not medical advice: Pregnancy, kidney disease, and medications need clinician guidance.

Frequently Asked Questions

Answers to common questions about this calculator.

What does vitamin k intake do in the body?

Clots blood properly and helps route calcium into bone instead of arteries. Clotting factors cannot activate without it.

How much vitamin K do I need per day?

The adequate intake (AI) is 120 mcg for men and 90 mcg for women. One serving of cooked greens delivers several days’ worth at once.

What are signs of low vitamin K?

Easy bruising and slow clotting mark shortfall — antibiotics plus low greens raise the risk.

Is there an upper limit for vitamin K?

No upper limit is set because food and standard supplements show no toxicity signal at normal doses, so no upper limit is set Still, more than the target buys nothing extra.

Which foods are richest in vitamin K?

Best bets: kale, spinach, collards, broccoli, natto, and soybean oil.

Do I need a vitamin K supplement?

Rarely needed. Multivitamin-level K suffices; warfarin users must keep intake steady and coordinated.

How do I absorb vitamin K better?

Eat K with some fat; gut bacteria also manufacture a share.

Who runs low on vitamin K most often?

Newborns, long-antibiotic users, and greens avoiders run low most often.

What is the difference between RDA and AI?

RDA is set when evidence pins the requirement precisely; AI is the best estimate when data are thinner. Both work as daily targets in this calculator.

What does the upper limit (UL) mean?

The highest daily intake likely safe for almost all adults. Crossing it does not guarantee harm, but risk rises — especially from supplements.

Should I count food and supplements together?

Yes. The body totals every source, so add fortified foods under food and every pill, powder, and gummy under supplements.

How accurate are intake estimates?

Within about 10–20% when portions are honest. Average 3–7 typical days rather than trusting one perfect day.

Do needs change with age or sex?

Often. Iron, calcium, and several vitamins carry different targets by sex or life stage — this calculator switches them automatically.

Can lab tests replace tracking?

Labs confirm status for nutrients like iron, B12, and vitamin D. Tracking shows habits; labs show stores — use both when numbers stay low.

Are food sources really better than pills?

Usually. Foods bundle fiber, co-factors, and slower release, while pills help only where diet or absorption falls short.

When should I re-check my intake?

After 2–4 weeks of consistent eating, any supplement change, or a new life stage such as pregnancy or older age.

Related Calculators

Explore more calculators related to this topic.

Related Guides

Deepen your understanding with these educational resources.

Eating for Micronutrient Coverage

Food-first strategies for the full vitamin and mineral panel.

Supplements: What Labels Hide

Elemental doses, stacking risks, and timing basics.

Building a Balanced Plate

Produce, protein, and whole grains in the right shares.

Glossary

Technical terms used in mortgage calculations explained in plain language.

AI: Adequate Intake: 120 mcg vitamin K daily for men, 90 mcg for women.
Upper Limit (UL): Upper Limit: none established — food and standard supplements show no toxicity signal.
% Daily Value: Label shorthand: share of a 2,000-calorie reference diet — useful but less precise than age- and sex-specific targets.
Warfarin interaction: Why steadiness beats avoidance: dose is tuned to usual K intake.
Elemental amount: The actual vitamin K inside a compound — the number this calculator wants.
Bioavailability: Share of an ingested nutrient the body can actually absorb and use.
Fortified food: Food with nutrients added during processing, such as iodized salt or fortified milk.
Deficiency vs insufficiency: Deficiency means clinical signs; insufficiency means low stores without symptoms yet.

Authoritative References

Trusted sources and standards referenced by this calculator.

NIH ODS — Vitamin K fact sheet U.S. Dietary Guidelines for Americans NIH Office of Dietary Supplements WHO — Healthy diet fact sheet FDA — Daily Value on nutrition labels Academy of Nutrition and Dietetics

Applicable Standards

Institute of Medicine Dietary Reference Intakes (DRI)NIH Office of Dietary Supplements fact sheetsU.S. Dietary Guidelines for Americans

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Page Information

Last Updated:

2026-09-15

Version:

2.0.0

References:

License:

Free to use for educational and professional purposes.