Function Health vs Rythm

What is Function Health, and what is Rythm?

Function Health and Rythm both start with a blood sample, and they differ on who collects it and how often it is repeated.

Function Health schedules two draws a year, collected at a partner lab or, in select locations, at home. Its clinicians review the numbers and write an analysis and action plan.

Rythm opens with "The World's Easiest Blood Test." A kit arrives monthly, you collect the sample yourself, and the results come from Rythm's own lab.

One is a pair of scheduled draws, and the other is a monthly kit you never leave home for.

What does Function Health include?

Function Health's $365 covers two draws, 160+ lab tests in total, clinician review of the results, and a dashboard that lays them out.

The company's four steps run like this:

1. Schedule tests — Fill in your health history and book the first appointment.
2. Get insights — Clinicians compare the results with your history to highlight what matters.
3. Take action — A retest every 3 to 6 months checks what has shifted.
4. Monitor for life — Your results stack up over time and expose trends early.

About 115 biomarkers come from the first draw. The second draw, mid-year, repeats around 60 of them and carries no extra fee. You can also question your results in Function's private AI chat, and SuppCo adds supplement guidance based on your numbers.

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What does Rythm include?

Rythm's subscription includes a monthly test kit, free sample pick-up, results in its app with a Rythm Score, and an AI Coach with no usage limit.

Rythm sums up the process in three steps:

1. At-Home Test — You apply the supplied collection device and fill the tubes.
2. Send (Mail or get picked up) — A FedEx pick-up is free, or you can drop the sample at a FedEx location.
3. Results within 2 days — Your numbers appear in the app once the lab has the sample.

Biological Age unlocks after your second completed test. Rythm's own CLIA-certified, CAP-accredited lab runs the samples, and members can share results with their own doctor as a PDF, a CSV, or a link.

What biomarkers do Function Health and Rythm measure in 2026?

One Rythm kit carries 27 or 28 biomarkers with no urinalysis, while Function Health's first draw counts 116 to 118, 20 of them urinalysis.

Rythm's headline is 25+ biomarkers. Its published list names 30, with separate panels for men and women, so by our count one member's kit carries 27 or 28.

Rythm's FAQ says the two panels exist because a single collection limits how many markers can be tested. Function's count includes urinalysis, and Rythm's list has none.

Function's add-ons include:

• Heart, thyroid, and autoimmunity — Heart risk beyond the baseline (genetic and metabolic), thyroid extensions, and celiac.
• Hormones, toxins, and nutrients — Extended hormone health, heavy metals, PFAS, and extended vitamins.
• Cancer, brain, and allergies — The GRAIL cancer test, Alzheimer's detection, and ApoE risk.
• Scans — Heart CT, lung CT, and MRI through Ezra.

Rythm says it offers no additional testing at the moment, with an add-on option on its roadmap.

What are the official 2026 membership prices for Function Health and Rythm?

Function Health costs $365 a year, while Rythm charges $79 a month for each test, plus shipping and tax.

Twelve monthly kits at $79 come to $948 a year before shipping and tax, against Function's $365 for two draws.

Rythm's subscription renews every 30 days, and members can skip up to 90 days without being charged. First-time buyers get a 90-day money-back guarantee. At Function, at-home draws exist in select locations at varying fees, and a New York or New Jersey state fee is paid at the facility. Both are HSA/FSA eligible.

Self-collected at home versus drawn at a lab

Rythm collects a capillary sample you take yourself, and Function Health draws blood at a lab or sends a phlebotomist in select locations.

Rythm's Tasso+ device is described by Rythm as FDA-cleared, and it fills standard tubes. Kits ship within a business day and arrive in two to three, and the return travels overnight by FedEx.

At Function, you travel to one of 2,000+ partner locations or request an at-home visit where offered. The trade is convenience on one side and a staffed draw on the other.

Monthly kits versus two draws a year

Rythm recommends testing every month, and Function Health schedules two draws.

Rythm's monthly tracking builds a picture over time, and it suggests at least three tests before skipping to a quarterly rhythm. Function's second draw repeats about 60 markers, and its steps point to retests every 3 to 6 months.

Frequent tests suit people watching one marker closely. Fewer, broader draws suit those who want a wide picture a couple of times a year.

Get 100+ biomarkers tested, in-lab or at home

One membership, one blood draw. Get a full picture of your health and the action plan you need to improve it.

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Get 100+ biomarkers tested, in-lab or at home

One membership, one blood draw. Get a full picture of your health and the action plan you need to improve it.

Book your testLoading...

How do Function Health and Rythm handle results and guidance?

Function Health puts clinician review between your results and your plan, and Rythm puts a physician sign-off before release and an AI Coach after it.

Function's first results typically arrive within 48 hours of testing, with the plan following after clinician review. Reviewers describe waits of three to four weeks for it.

Rythm's results arrive within 2 days of the sample reaching the lab, which Rythm credits to its smaller set of biomarkers. A state-licensed physician signs off before release. Rythm's guidance is informational and it does not prescribe.

Where are Function Health and Rythm tests available?

Function Health draws at 2,000+ locations across 48 states, leaving out Hawaii, Rhode Island, and Puerto Rico.

Rythm is available in all 50 states to anyone with a US shipping address that FedEx can reach. It does not ship abroad.

Who is Function Health best for, and who is Rythm best for?

Function Health is best for:

• People who want clinician review of their results.
• People who want a broader panel from each draw.
• People who want one flat annual price.

Rythm is best for:

• People who want to test from home with no lab visit.
• People who want a monthly cadence, with the freedom to skip.
• People in any of the 50 states, including those Function leaves out.

The bottom line

Function Health and Rythm both give you blood data and a way to read it. Function offers two draws, a broader panel, and clinician review for $365. Rythm offers a monthly home kit and quick results at $79 each.

Both models end at guidance. Neither offers prescriptions, and each points to supplements without selling them, through Function's SuppCo advice and Rythm's in-app suggestions.

Superpower carries on past guidance at $199 a year in most states, below both Function's $365 and the $948 a year of monthly Rythm kits. Its marketplace stocks supplements at up to 20% off and add-on tests and scans such as DEXA, VO2 max, and whole-body MRI, with prescriptions available when clinically appropriate, priced separately. Superpower AI drafts the Superpower Protocol out of your lab results, wearable feeds, and records, then rewrites it as new data comes in, with AI and care team support for questions along the way. Superpower reports that 93% of members found their action plan more useful, even life-changing, than a yearly checkup.

Blood work is where a health plan starts, not where it ends. Build your home for health with Superpower today.