Reconcile one completed two-feedstock compost mix from as-received masses and same-basis dry-matter, total-carbon and total-nitrogen analyses.
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Inputs that matter
One de-identified completed owner, operator or reviewed-training two-feedstock compost-mix record; responsible source/revision/date; system/stage/intended use; both feedstock identities/lots/sample states; representative sampling and laboratory methods; same-unit scale/tare/container record; moisture/dry-matter and total-carbon/total-nitrogen bases; structure/blending, contamination, process, pathogen/vector/odor, legal/program, tolerance/review/retention records; one mass unit; as-received mass plus dry-matter, total-carbon and total-nitrogen percentages for Material A and B; completed five-total source record; and an optional same-basis independent source with five totals
Output to expect
Each feedstock's reproduced dry matter, water, total carbon and total nitrogen; combined as-received mass, dry matter, water, wet-basis moisture, total carbon, total nitrogen and C:N; completed mass/moisture/reported-ratio/internal-ratio differences; and optional independent same-basis differences
How it works
Validate every provenance field, exact choice and bounded value; require each dry-matter, total-carbon and total-nitrogen percentage above zero and no more than 100%, with carbon plus nitrogen no more than dry matter; convert each as-received mass to dry matter, then to carbon and nitrogen mass; add constituent masses before dividing total carbon by total nitrogen; require completed and optional independent dry matter no greater than as-received and carbon plus nitrogen no greater than dry matter; compare without clamping; and normalize only mathematical zero
Confirm that both feedstocks, source lots, as-received/sample states, sampling and analytical methods, mass unit, scale/tare/container basis, completed record and independent record all match. Another feedstock, sample, method, unit, batch, stage or revision needs another run.
Use the result only for one completed two-feedstock same-basis mass/analysis and transcription check. It does not choose feedstocks or assumed composition; set a C:N or moisture target; recommend additions; validate structure, blending, contamination, moisture/oxygen/temperature/time/turning or pathogen controls; establish stability, maturity, law or tolerance; handle more than two feedstocks; or authorize mixing, sale, application or crop use.
Choose your path
Built around the job you need to finish
Reconcile one completed two-feedstock compost-mix mass record from source-owned as-received masses and same-state dry-matter, total-carbon and total-nitrogen analyses without issuing a recipe, process, stability, safety or use approval.
Owner checking one documented two-feedstock mix
Replace generic brown/green assumptions with the exact feedstock samples and mass records used for one completed mix.
Freeze both feedstock identities and states, representative analyses, one mass unit and the completed total record before entering values.
Sees reproduced dry matter, moisture, carbon, nitrogen and C:N plus signed completed differences without an adjustment recommendation.
Operator reconciling laboratory and scale records
Detect a wet/dry basis, unit, tare or transcription mismatch before a completed record is accepted.
Align sample state, analytical methods, dry-basis constituent percentages and same-unit masses, then inspect completed totals and internal C÷N consistency.
Gets explicit as-received, dry-matter, moisture, carbon, nitrogen, reported-ratio and internal-ratio differences while process decisions stay external.
Compost or food-safety reviewer checking an independent record
Prevent another feedstock, sample, method, unit, tare basis or revision from being presented as corroboration.
Enter the optional independent source and all five totals only when both feedstocks and every analytical/mass basis align.
Receives all-or-none validation and separate independent differences without a stability, pathogen, regulatory or crop-use conclusion.
Authoritative checks for this tool
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
Identify Material A and Material B by source, lot, as-received state and sampling time. Retain representative sampling, laboratory methods and report revisions; a typical brown/green table is not a measurement of either feedstock.
Move every analysis to a mass basis
Multiply each as-received mass by its dry-matter fraction. Then multiply that dry mass by total carbon and total nitrogen percentages reported on the same dry basis.
dry mass = as-received mass × dry-matter fraction; constituent mass = dry mass × dry-basis fraction
Add masses before dividing
Add water, dry matter, total carbon and total nitrogen across both feedstocks. Reproduce wet-basis moisture from combined water divided by combined as-received mass, and reproduce C:N from total carbon mass divided by total nitrogen mass.
mix C:N = sum of carbon mass / sum of nitrogen mass
Reconcile completed and independent totals
Enter the completed total masses and reported C:N separately so transcription and internal C÷N consistency remain visible. An optional independent record must supply its source and all five same-basis totals together.
Updated: August 2026
Example Scenarios
Copy both current feedstock analysis records and measured as-received masses, then compare the reproduced totals with the completed batch record without accepting a recipe target.
Align sampling state, laboratory basis, scale/tare and units before using signed dry-matter, moisture, carbon, nitrogen and C:N differences to investigate transcription.
Enter an optional independent source only when the exact two feedstocks, sample states, analytical methods, mass unit, tare basis and record revision match.
Common Mistakes to Avoid
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Averaging the two input C:N ratios or weighting them by wet mass
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Convert each feedstock's same-state dry-matter, carbon and nitrogen analyses into constituent masses, add carbon and nitrogen separately, then divide the totals.
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Mixing wet-basis and dry-basis percentages
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Retain the stated analytical basis. This workflow expects dry matter as a percentage of as-received mass and total carbon/total nitrogen as percentages of dry matter.
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Treating a matching ratio as process or use approval
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Keep feedstock acceptance, structure, mixing, moisture/oxygen/temperature/time/turning, pathogens, contamination, program rules, tolerance, release and application decisions with their responsible records.
FAQ
No. It reproduces the C:N of one completed two-feedstock source record. Feedstock choice, target range and adjustments remain with the responsible compost process and intended-use authority.
Water adds to scale mass but not to dry-basis carbon and nitrogen totals. The dry-matter fraction puts both feedstocks on an aligned constituent-mass basis before their carbon and nitrogen are combined.
Not in this reviewed workflow. It requires total carbon and total nitrogen percentages on the same dry basis for each exact sampled feedstock; generic tables cannot establish the sampled material's composition.
No. C:N is not a stand-alone stability or maturity indicator, and it does not validate moisture, oxygen, temperature, time, turning, pathogen reduction, curing, contamination or intended-use requirements.
Yes, if every input and compared record uses kilograms. The C:N ratio is unitless, but all mass totals and differences must use one aligned unit.
No. It is intentionally limited to one completed two-feedstock record. A larger recipe, staged addition, amendment or water addition requires another reviewed method and process record.
About Reviewed Compost Mix Record
Reproduce one completed two-feedstock mix record without turning arithmetic into a recipe or safety decision. Freeze both feedstock identities and sample states, representative analytical methods, one mass unit and the completed totals; then review dry matter, wet-basis moisture, carbon, nitrogen and C:N differences with the person who owns the process and release.