| Form N-CSR Cover | 6 Months Ended |
| Oct. 31, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS |
| Amendment Flag | false |
| Registrant Name | Putnam ETF Trust |
| Entity Central Index Key | 0001845809 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Oct. 31, 2024 |
| Shareholder Report | 6 Months Ended | |
| Oct. 31, 2024 USD ($) $ / shares | ||
| Shareholder Report [Line Items] | ||
| Document Type | N-CSRS | |
| Amendment Flag | false | |
| Registrant Name | Putnam ETF Trust | |
| Entity Central Index Key | 0001845809 | |
| Entity Investment Company Type | N-1A | |
| Document Period End Date | Oct. 31, 2024 | |
| Putnam PanAgora ESG International Equity ETF | ||
| Shareholder Report [Line Items] | ||
| Fund Name | Putnam PanAgora ESG International Equity ETF | |
| Class Name | Putnam PanAgora ESG International Equity ETF | |
| Trading Symbol | PPIE | |
| Security Exchange Name | NYSE | |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about Putnam PanAgora ESG International Equity ETF for the period May 1, 2024, to October 31, 2024. | |
| Shareholder Report Annual or Semi-Annual | semi-annual shareholder report | |
| Additional Information [Text Block] | You can find additional information about the Fund at https://www.franklintempleton.com/regulatory-fund-documents . You can also request this information by contacting us at (800) DIAL BEN/342-5236 . | |
| Additional Information Phone Number | (800) DIAL BEN/342-5236 | |
| Additional Information Website | https://www.franklintempleton.com/regulatory-fund-documents | |
| Expenses [Text Block] | WHAT WERE THE FUND COSTS FOR THE LAST SIX MONTHS? (based on a hypothetical $10,000 investment) Fund Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment * , † Putnam PanAgora ESG International Equity ETF $26 0.49% | [1],[2] |
| Expenses Paid, Amount | $ 26 | |
| Expense Ratio, Percent | 0.49% | |
| Net Assets | $ 202,030,593 | |
| Holdings Count | $ / shares | 91 | [3] |
| Investment Company Portfolio Turnover | 35% | |
| Additional Fund Statistics [Text Block] | KEY FUND STATISTICS (as of October 31, 2024) Total Net Assets $202,030,593 Total Number of Portfolio Holdings * 91 Portfolio Turnover Rate 35% | [3] |
| Holdings [Text Block] | [4] | |
| Updated Prospectus Web Address | https://www.franklintempleton.com/regulatory-fund-documents | |
| [1] * Reflects fee waivers and/or expense reimbursements, without which expenses would have been higher. † Annualized. * Includes derivatives, if applicable. Cash and Equivalents, if any, represent the market value weights of cash, derivatives, short-term securities, and other unclassified assets in the portfolio. Holdings and allocations may vary over time. | ||
| Label | Element | Value |
| Putnam PanAgora ESG International Equity ETF | Other Countries [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3% |
| Putnam PanAgora ESG International Equity ETF | Cash and Equivalent [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 0.50% |
| Putnam PanAgora ESG International Equity ETF | Japan | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 24.10% |
| Putnam PanAgora ESG International Equity ETF | United Kingdom | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 13.80% |
| Putnam PanAgora ESG International Equity ETF | France | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 12.10% |
| Putnam PanAgora ESG International Equity ETF | Switzerland | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 8.40% |
| Putnam PanAgora ESG International Equity ETF | Australia | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 8% |
| Putnam PanAgora ESG International Equity ETF | Germany | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 7.90% |
| Putnam PanAgora ESG International Equity ETF | Denmark | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.40% |
| Putnam PanAgora ESG International Equity ETF | Netherlands | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 4.10% |
| Putnam PanAgora ESG International Equity ETF | Italy | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 3.50% |
| Putnam PanAgora ESG International Equity ETF | Sweden | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.50% |
| Putnam PanAgora ESG International Equity ETF | Finland | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2.10% |
| Putnam PanAgora ESG International Equity ETF | Spain | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 2% |
| Putnam PanAgora ESG International Equity ETF | Czech Republic | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 1.60% |
| Putnam PanAgora ESG International Equity ETF | Ireland | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 1.10% |
| Putnam PanAgora ESG International Equity ETF | Norway | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Net Asset Value | oef_PctOfNav | 0.90% |
