をもとに（して）・
Choosing a source, basis, standard, or premise
The key question is what the first noun contributes to what follows. Is it material transformed into something new, firm grounds for a decision, earlier information that shapes the next response, a standard used to judge a case, or an assumption on which a plan depends? English often calls all five relationships “based on,” but Japanese keeps them distinct.
One noun, five possible roles
These expressions do not merely attach a vague source to a result. They describe a particular relationship between the source and the later action or judgment. First identify that relationship; the appropriate form usually follows naturally.
Choose by the role of the source
Ask which description best matches what you mean.
Material or model
をもとに（して）
A source, model, memory, record, or body of data is used to create, reconstruct, design, or explain something new.
The new result may reorganize or substantially change the original material; it need not be an exact copy.
Firm grounds
に基づいて
Evidence, facts, rules, principles, plans, or professional experience support and justify a claim, decision, or controlled action.
This presents a stronger, more defensible basis than loose inspiration or background information.
Earlier information carried forward
を踏まえて
Results, feedback, experience, criticism, or previous discussion are taken into account, and the next action responds to what they show.
Simply knowing the earlier information is not enough; its implications should affect what follows.
Benchmark for evaluation
に照らして
A law, criterion, precedent, accepted norm, established fact, or body of evidence is used as a benchmark for judging a separate case.
There must be an understandable comparison between the benchmark and the matter being evaluated.
Assumption or required condition
を前提に
A plan, design, agreement, explanation, or relationship is built on a working assumption or a condition that must hold.
The premise may concern the future or remain unproven; the form does not claim that evidence has established it as true.
Creating from material or deciding from evidence?
A research team has historical records and verified measurements available for different tasks.
古い航海日誌をもとに、港の歴史を紹介する映像を制作した。
They created a video introducing the port’s history from old ship logs.
AnalyzeThe logs are source material transformed into a new work.
最新の測定結果に基づいて、港の使用制限を決定した。
They determined the port’s operating restrictions based on the latest measurements.
AnalyzeThe measurements provide defensible grounds for an official decision.
Takeaway: Use the material expression when the source is developed into a new product. Use the grounding expression when the source supports or authorizes a conclusion or action.
Responding to information or judging against a standard?
An organization is reviewing a service after receiving complaints.
利用者からの苦情を踏まえて、受付方法を変更した。
Taking user complaints into account, the organization changed its reception procedure.
AnalyzeThe complaints lead to a responsive change.
新しい運用基準に照らして、現在の受付方法は不適切だと判断された。
Judged against the new operating standards, the current reception procedure was found inappropriate.
AnalyzeThe standards are a benchmark, and the current procedure is the separate case being evaluated.
Takeaway: The responsive form asks, “What should we now do because of what we learned?” The benchmark form asks, “How does this case measure up against the standard?”
Established grounds or an assumed condition?
A company is preparing a budget for a new service.
昨年度の実績に基づいて、必要な人員を算出した。
The company calculated the necessary staffing based on last year’s performance.
AnalyzeExisting results supply the grounds for the calculation.
利用者が毎月増えることを前提に、来年度の予算を組んだ。
The company prepared next year’s budget on the assumption that the number of users would increase each month.
AnalyzeFuture growth is a working assumption built into the budget, not an established fact.
Takeaway: Grounding points backward to facts or authority already available. A premise sets the condition under which the later plan is designed to work.
More examples across the family
試験飛行の記録をもとに、新しい訓練教材を作った。
They created new training materials from the test-flight records.
Analyze研究班は測定結果に基づいて、装置の性能を評価した。
The research team evaluated the device’s performance based on the measurement results.
Analyze会議で出た懸念を踏まえて、公開日を延期した。
Taking the concerns raised at the meeting into account, they postponed the release date.
Analyze前年度の反省を踏まえた運営方針が発表された。
An operating policy reflecting lessons from the previous year was announced.
Analyze契約条件に照らして、この請求は認められない。
Judged against the contract terms, this claim cannot be accepted.
Analyze停電が二時間続くことを前提に、訓練計画を作成した。
They prepared the drill plan on the assumption that a power outage would last two hours.
Analyze全員が守秘義務を守ることを前提として、資料を共有する。
The materials will be shared on the condition that everyone observes the confidentiality requirement.
Analyze