Uric Acid (Urate) Unit Converter
Uric Acid (Urate) Unit Converter
Convert urate between mg/dL, µmol/L and mmol/L — and keep two different numbers apart: the sex-specific reference interval, and the 360 µmol/L treat-to-target used in gout.
Uric Acid (Urate) converter
Mass ⇄ molarSerum urate 5.4 mg/dL in an adult man
Formula and conversion factors
mg/dL = µmol/L ÷ 59.4849
mmol/L = µmol/L ÷ 1000
- 59.4849
- derived from the molecular mass of uric acid, 168.11 Da: 1 mg/dL is 0.01 g/L, and 0.01 ÷ 168.11 mol/L is 59.4849 µmol/L
- 6.0 mg/dL = 357 µmol/L
- the gout treat-to-target, universally rounded to 360 µmol/L in SI-reporting countries — the same threshold expressed twice, not two thresholds
- reference interval
- a population range describing what most healthy people have; it is sex-specific and it is not a treatment target
- saturation
- monosodium urate begins to crystallise above roughly 380–405 µmol/L (about 6.4–6.8 mg/dL); the 360 µmol/L target is set deliberately below that
Worked example
Serum urate 5.4 mg/dL in an adult man
5.4 × 59.4849 = 321 µmol/L
= 0.321 mmol/L
Within the male reference interval of 200–430 µmol/L
And below the gout treat-to-target: 6.0 mg/dL × 59.4849 = 357 µmol/L, conventionally quoted as 360
Thresholds across the units
| mg/dL | µmol/L | mmol/L | |
|---|---|---|---|
| Adult men, reference interval | 3.4 – 7.2 | 200 – 430 | 0.20 – 0.43 |
| Adult women, reference interval | 2.4 – 6.1 | 140 – 360 | 0.14 – 0.36 |
| Approximate saturation point for monosodium urate | 6.4 – 6.8 | 380 – 405 | 0.38 – 0.41 |
| Treat-to-target in gout | < 6.0 | < 360 | < 0.36 |
| Lower target with tophi or frequent flares | < 5.0 | < 300 | < 0.30 |
The reference interval is not the target
| Reference interval | Treat-to-target | |
|---|---|---|
| What it is | The range covering most healthy people of that sex | The urate level below which crystals dissolve and flares stop |
| Where it comes from | The issuing laboratory’s own population data | Gout guidelines: ACR 2020, EULAR 2016, NICE NG219 |
| Typical figure | Up to about 430 µmol/L in men | Below 360 µmol/L, or below 300 with tophi |
| Applies to | Anyone having a urate measured | People with gout on urate-lowering therapy |
| Consequence of confusing them | A man with gout at 400 µmol/L is called ‘normal’ and left under-treated | Nobody without gout needs treating to a number |
Two thresholds that are constantly confused
Urate is reported in mg/dL in the United States and in µmol/L almost everywhere else, with mmol/L appearing occasionally. The conversion comes straight from the molecular mass of uric acid, 168.11 daltons: one mg/dL is 59.4849 µmol/L. Serum urate and serum uric acid are the same test under two names, and nothing about the analysis differs between them.
The important content on this page is not the arithmetic but a distinction that gets lost constantly. The reference interval is a population range: roughly 200 to 430 µmol/L in men and 140 to 360 µmol/L in women, describing what most healthy people of that sex have. The treat-to-target in gout is a different quantity entirely — below 360 µmol/L, or 6.0 mg/dL, and below about 300 µmol/L where there are tophi or frequent flares. It sits inside the male reference interval, which means a man with gout can have a urate reported as perfectly normal while remaining well above the level at which his crystals will dissolve. Treating him to a reference interval rather than to the target is a common and consequential error.
The target is chosen with a margin. Monosodium urate begins to crystallise in tissue somewhere around 380 to 405 µmol/L, about 6.4 to 6.8 mg/dL, depending on temperature and local conditions — which is why gout favours the cool peripheral joints. A target of 360 µmol/L sits deliberately below that saturation point so that existing deposits dissolve rather than merely stop growing.
Two further points prevent avoidable mistakes. A normal urate does not exclude gout: the level often falls during an acute attack, so a normal result from a hot swollen joint is worth nothing, and the diagnosis rests on aspiration and polarised microscopy where it genuinely matters. And a raised urate is not, on its own, a disease. Most people with asymptomatic hyperuricaemia never develop gout, and no major guideline recommends treating the number alone. Chronic kidney disease, thiazide and loop diuretics, ciclosporin, alcohol and a high-purine diet all raise it, and a markedly raised urate in someone starting chemotherapy raises the separate question of tumour lysis.
Frequently asked questions
How do I convert uric acid from mg/dL to µmol/L?
Multiply by 59.4849, a factor derived from the molecular mass of uric acid, 168.11 daltons. A urate of 5.4 mg/dL is 321 µmol/L, and 6.0 mg/dL is 357 µmol/L — the figure normally quoted as 360.
What is a normal uric acid level?
Roughly 200 to 430 µmol/L (3.4 to 7.2 mg/dL) in adult men and 140 to 360 µmol/L (2.4 to 6.1 mg/dL) in adult women, with the female interval rising towards the male one after the menopause. Intervals are laboratory-specific, so use the one on the report.
Is the gout target the same as the normal range?
No, and confusing them is the commonest error here. The treat-to-target in gout is below 360 µmol/L (6.0 mg/dL), which sits inside the male reference interval. A man with gout at 400 µmol/L is within the reference interval and above the target at the same time.
Can I have gout with a normal uric acid?
Yes. Serum urate frequently falls during an acute attack, so a normal or even low result taken from someone with a hot swollen joint does not exclude gout. Where the diagnosis matters, joint aspiration with polarised microscopy for monosodium urate crystals settles it.
Does a high uric acid need treating?
Not by itself. Most people with asymptomatic hyperuricaemia never develop gout, and no major guideline recommends urate-lowering therapy for the number alone. Treatment is directed at established gout, and then to a target rather than into the reference interval.
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References
- FitzGerald JD, Dalbeth N, Mikuls T, et al. 2020 American College of Rheumatology guideline for the management of gout. Arthritis Care Res. 2020;72(6):744–760.
- Richette P, Doherty M, Pascual E, et al. 2016 updated EULAR evidence-based recommendations for the management of gout. Ann Rheum Dis. 2017;76(1):29–42.
- National Institute for Health and Care Excellence. Gout: diagnosis and management. NICE guideline NG219. London: NICE; 2022.
Medical Disclaimer: The tools and content provided here are for educational and reference purposes only. They are not intended to substitute for professional medical advice, diagnosis, or treatment. Clinical decisions should always be based on the comprehensive assessment of a qualified healthcare professional.