What the Mk 677 record shows

Evidence through 2026-09-18

TitrateLab tracks 27 published Mk 677 certificate-of-analysis source records through 2026-09-18, each with a recorded purity or measured-versus-label amount result. Across 16 records with a numeric peptide-purity result, including zero, the median reported purity is 99.1%. Across 18 records with measured-versus-label dose data, 61% are within 10% of the labeled quantity. This is a public convenience sample, not a randomized market survey; one result describes one submitted sample and does not verify other batches.

Published records with a non-null purity or measured-versus-label amount result. Matching uses a normalized compound slug. No deduplication in this archive summary; relays and corrected records can remain separate. Records with neither measurement are excluded here, but can appear in the research overview's exact-token raw-record total. These are not unique certificates or batches. TitrateLab indexes reports from third-party laboratories.

Aggregate calculated: 2026-10-02T13:55:01.517541+00:00. Calculation time is not a test date.

Published records27
Reported purity99.1% median · 16 results
Dose accuracy61% within ±10% · 18 results
EndotoxinNot reported
Evidence dates2020-06-16 to 2026-09-18
Limits and missing evidence
  • No classifiable endotoxin results were recorded.
  • The testing laboratory is unattributed on 1 record.
  • Coverage depends on reports that were published and available to ingest.
Assay metrics

Mk 677 lab-testing metrics

27
Certificates
99.1%
Median reported purity (zero included)
75%
Purity records ≥ 99%
0
Source records reporting zero purity
2
Testing labs
17
Vendors
Mean purity98.6% Below 90% purity0% Mean dose vs label-19.5% Underfilled28% Within 10% of label dose61% Overdosed ≥ +7%22% Underdosed ≤ −7%28%

COAs per testing lab

Every lab testing Mk 677 in the corpus.

Freedom Diagnostics 20 99.4% med
Janoshik 6 97% med
Unattributed / lab unknown 1 99.3% med

Tested-purity distribution

Bins below 90% tested purity (0% of numeric purity records).

Mk 677 tested-purity distribution
Purity rangeCertificates
0–50%0
50–70%0
70–80%0
80–85%0
85–90%0
90–91%0
91–92%0
92–93%0
93–94%1
94–95%0
95–96%0
96–97%1
97–98%0
98–99%2
99–100%12

COAs over time

Mk 677 source records by test month (discovery month when test date is absent).

Mk 677 certificates per month
MonthCertificates
2020-061
2022-121
2023-071
2024-121
2025-051
2026-021
2026-032
2026-054
2026-061
2026-073
2026-084
2026-097

Most-tested vendors

Top 10 of 15 vendors by Mk 677 certificate count.

TitrateLab ProVendor names in this chart are hidden. Lab-report counts are free.Vendor namesOriginal COAsBatch detailsBuyer reviewsPrice and stock alertsSee vendor names with Pro
Vendor name available with ProExplore reports + 4

Lab evidence

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4 lab reports from this vendor

This chart compares report counts for this compound. A larger test history does not establish better purity, dose accuracy or endotoxin results. Inspect the individual reports to compare measurements.

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Vendor name available with ProExplore reports + 2

Lab evidence

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Lab evidence

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Explore this vendor’s lab reports

Pick a compound, then a report, to see what the lab measured. Each report counts once, and only reports with a source link and a readable result appear here, so this list can hold fewer reports than the total above.

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Lab evidence

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2 lab reports from this vendor

This chart compares report counts for this compound. A larger test history does not establish better purity, dose accuracy or endotoxin results. Inspect the individual reports to compare measurements.

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Pro shows the vendor’s name, its original lab reports and batch details.

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Vendor name available with ProExplore reports + 1

Lab evidence

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Explore this vendor’s lab reports

Pick a compound, then a report, to see what the lab measured. Each report counts once, and only reports with a source link and a readable result appear here, so this list can hold fewer reports than the total above.

TitrateLab Pro Which vendor is this?

Pro shows the vendor’s name, its original lab reports and batch details.

Vendor behind these reportsVendor name available with Pro
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  • Vendor names on every ranking and chart
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Vendor name available with ProExplore reports + 1

Lab evidence

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1 lab reports from this vendor

This chart compares report counts for this compound. A larger test history does not establish better purity, dose accuracy or endotoxin results. Inspect the individual reports to compare measurements.

TitrateLab Pro Which vendor is this?

Pro shows the vendor’s name, its original lab reports and batch details.

Vendor behind these reportsVendor name available with Pro
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  • Vendor names on every ranking and chart
  • Original COAs with batch details
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See vendor names with Pro Names, original COAs and batch details

Monthly or lifetime plans. Monthly cancels anytime. Compare plans

Vendor name available with ProExplore reports + 1

Lab evidence

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1 lab reports from this vendor

This chart compares report counts for this compound. A larger test history does not establish better purity, dose accuracy or endotoxin results. Inspect the individual reports to compare measurements.

TitrateLab Pro Which vendor is this?

Pro shows the vendor’s name, its original lab reports and batch details.

Vendor behind these reportsVendor name available with Pro
What Pro unlocks
  • Vendor names on every ranking and chart
  • Original COAs with batch details
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See vendor names with Pro Names, original COAs and batch details

Monthly or lifetime plans. Monthly cancels anytime. Compare plans

Vendor name available with ProExplore reports + 1

Lab evidence

Free preview

1 lab reports from this vendor

This chart compares report counts for this compound. A larger test history does not establish better purity, dose accuracy or endotoxin results. Inspect the individual reports to compare measurements.

TitrateLab Pro Which vendor is this?

Pro shows the vendor’s name, its original lab reports and batch details.

Vendor behind these reportsVendor name available with Pro
What Pro unlocks
  • Vendor names on every ranking and chart
  • Original COAs with batch details
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See vendor names with Pro Names, original COAs and batch details

Monthly or lifetime plans. Monthly cancels anytime. Compare plans

Vendor name available with ProExplore reports + 1

Lab evidence

Free preview

1 lab reports from this vendor

This chart compares report counts for this compound. A larger test history does not establish better purity, dose accuracy or endotoxin results. Inspect the individual reports to compare measurements.

TitrateLab Pro Which vendor is this?

Pro shows the vendor’s name, its original lab reports and batch details.

Vendor behind these reportsVendor name available with Pro
What Pro unlocks
  • Vendor names on every ranking and chart
  • Original COAs with batch details
  • Buyer reviews for each vendor
  • Price and stock alerts for your watchlist
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See vendor names with Pro Names, original COAs and batch details

Monthly or lifetime plans. Monthly cancels anytime. Compare plans

Vendor name available with ProExplore reports + 1

Lab evidence

Free preview

1 lab reports from this vendor

This chart compares report counts for this compound. A larger test history does not establish better purity, dose accuracy or endotoxin results. Inspect the individual reports to compare measurements.

TitrateLab Pro Which vendor is this?

Pro shows the vendor’s name, its original lab reports and batch details.

Vendor behind these reportsVendor name available with Pro
What Pro unlocks
  • Vendor names on every ranking and chart
  • Original COAs with batch details
  • Buyer reviews for each vendor
  • Price and stock alerts for your watchlist
  • Ask Titer, the AI research assistant
See vendor names with Pro Names, original COAs and batch details

Monthly or lifetime plans. Monthly cancels anytime. Compare plans

+ 5 more vendors with fewer certificates.

Published Mk 677 certificates of analysis

27 records. Zero guesswork.

Unlock the actual vendor, purity, dose accuracy, lab, batch and saved certificate for every Mk 677 result.

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Illustrative structure only. No record-level values are present in this preview.

Reading Mk 677 lab reports

A valid report describes the sample that was submitted, not every vial sold under the same name. Guide: How to verify and read a peptide COA: 5 checks.

TitrateLab analysis mentioning Mk 677

More COA results by compound