～かねる and ～かねない: opposite meanings, one stem

～かねる means “cannot” or “find it difficult to,” often in a polite refusal. ～かねない means “might well” or “could,” usually warning of an unwanted result; its ない does not simply cancel the first meaning. Both follow a verb’s ます-stem, so the ending, not the stem, tells you which message the sentence sends.

Ask whether the clause declines an action or warns of a result

Imagine a service desk replying to a request for a last-minute change:

その変更には応じかねます。
そのへんこうには おうじかねます。
We cannot accommodate that change.

The desk is declining its own action, 応じる (“accommodate”). A second line can explain why:

直前の変更は混乱を招きかねません。
ちょくぜんの へんこうは こんらんを まねきかねません。
A last-minute change could cause confusion.

The change is the subject of 招く (“bring about”). Nobody is declining to cause confusion: the writer is warning that confusion is possible. In connected text, identify whose action is at issue before translating the ending.

Ending after the ます-stem	Meaning here	Typical setting	Form and reading
～かねる / ～かねます	Cannot or finds it difficult to act	Considered decision; often a formal refusal	応じかねます（おうじかねます）
～かねない / ～かねません	Might act or cause a result; often unwelcome	Warning or risk assessment	招きかねません（まねきかねません）

The Bunpro page for ～かねる and its ～かねない page give the ます-stem attachment and opposing senses. JLPT Sensei’s ～かねる lesson and ～かねない lesson independently describe the central distinction. The risk ending usually concerns an unwelcome outcome; it is not an absolute “bad things only” rule.

Keep the ます-stem when the meaning turns

Remove ます from the polite verb before adding either ending. 答える becomes 答えます, then 答えかねます; 招く becomes 招きます, then 招きかねません. The verb-group guide explains how to find the stem.

Dictionary form	ます-form	Stem	Refusal/difficulty	Risk/possibility
答える（こたえる）	答えます	答え	答えかねます	答えかねません
招く（まねく）	招きます	招き	招きかねます	招きかねません

The last two columns demonstrate form, not a recommendation to use every combination in a notice. A desk may decline to answer, while a change may cause trouble. Choose a natural verb and situation first, then attach the ending.

～かねる has a decision or difficulty behind the refusal

この資料だけでは判断しかねます。
このしりょうだけでは はんだんしかねます。
I cannot make a judgment from this document alone.

The speaker does not lack the physical ability to judge. The available material does not support a responsible decision. その質問にはお答えしかねます（そのしつもんには おこたえしかねます）similarly declines to answer a particular question. JLPT Sensei also gives 決めかねている, a person who is still unable to decide, so the pattern is wider than customer-service replies.

できない is broader. A broken printer gives you 印刷できません, a direct statement of inability to print. A proposed change can elicit 応じかねます, the speaker’s considered limit. Calling every ～かねる “polite できない” loses that difference.

～かねない raises a possibility you want to avoid

確かめずに公開すると、誤解を招きかねません。
たしかめずに こうかいすると、ごかいを まねきかねません。
Publishing it without checking could cause a misunderstanding.

The clause before the comma gives the condition; ～かねません evaluates the possible consequence. It does not say misunderstanding will happen. The writer sees a risk worth mentioning, but the outcome remains open. Bunpro and JLPT Sensei both use this possibility sense with negative consequences in their linked ～かねない lessons.

An ordinary negative reverses the meaning: 混乱を招きません says “it does not cause confusion”; 混乱を招きかねません says “it could cause confusion.” In a notice, that difference can reverse the reader’s understanding of a proposed action.

The same situation allows two claims, not two translations

The service-desk pair illustrates the overlap: a request is declined because the change may cause trouble. ～かねる names the desk’s limit; ～かねない names the possible result. The endings do not substitute for one another while preserving the claim.

This is N2 grammar in the Kikusho curriculum, with a level-label caveat. Bunpro and JLPT Sensei put both forms on N2 pages, while N1et’s teaching comparison places ～かねる at N3. The JLPT FAQ leaves learners without a complete official catalogue of grammar points for each level. The prerequisite is the ます-stem; the skill at either level is reading a refusal and a warning as different claims.

If you save a real reply in Kikusho, keep the whole sentence on the card. The subject and possible consequence tell you why ～かねない is a warning, while a register note preserves where ～かねます suited a desk reply. The formal connectors lesson helps you read the rest of a notice around it.

Practice: choose the claim each sentence needs

Try all six questions before opening the answer section.

Question 1

A staff member has only one page of an application and cannot decide yet. Choose the ending.

この一枚だけでは、合否を判断し＿＿＿。

• A. かねます
• B. かねません
• C. ません

Question 2

A notice warns that an unchecked translation may mislead readers. Choose the ending.

訳を確認せずに載せると、読者の誤解を招き＿＿＿。

• A. かねます
• B. かねません
• C. ません

Question 3

Build a formal reply meaning “We cannot accommodate that request at present.” Use every piece once.

現時点では ・ そのご依頼には ・ 応じ ・ かねます

Question 4

Build a warning meaning “If this is left as it is, it could cause confusion.” Use every piece once.

このままにすると ・ 混乱を ・ 招き ・ かねません

Question 5

Read the two-sentence memo, then choose the interpretation.

追加の情報がないため、その質問にはお答えしかねます。推測で説明すると、誤解を招きかねません。

• A. The writer can answer now and promises there will be no misunderstanding.
• B. The writer declines to answer and warns that guessing could mislead.
• C. The writer says it is impossible for anyone to misunderstand.

Question 6

A manager writes この案は混乱を招きかねません in a report. Which replacement would turn the warning into a statement that confusion does not result?

• A. この案は混乱を招きません。
• B. この案は混乱を招きかねます。
• C. この案は混乱を招きかねない。

Answers and explanations

Answer 1

A: かねます. 判断しかねます（はんだんしかねます）presents the staff member’s present difficulty deciding from one page. B says a judgment might occur, often with an unwelcome implication. C makes 判断しません, a direct choice not to judge, without the stated difficulty.

Answer 2

B: かねません. 誤解を招きかねません（ごかいを まねきかねません）warns that an unchecked translation may cause misunderstanding. A says the subject cannot bring one about; C says it does not bring one about. Neither conveys the warning.

Answer 3

現時点では、そのご依頼には応じかねます。（げんじてんでは、そのごいらいには おうじかねます。）The stem 応じ stays directly beside かねます; 現時点では limits the refusal to the present. Replacing the ending with かねません would make a possibility claim.

Answer 4

このままにすると、混乱を招きかねません。（このままにすると、こんらんを まねきかねません。）The condition comes first. 招き, the ます-stem of 招く, takes the possibility ending; ～かねます would describe difficulty causing confusion.

Answer 5

B. お答えしかねます（おこたえしかねます）declines to answer without enough information. 誤解を招きかねません（ごかいを まねきかねません）adds the possible harm of explaining by guesswork. A reverses both endings; C treats the warning as a guarantee that misunderstanding cannot occur.

Answer 6

A. 招きません（まねきません）is an ordinary negative: the plan does not cause confusion. B claims difficulty causing confusion; C is a plain-style version of the original warning. The ending’s ない does not make C reassuring.