Free Stock OHLCV API
for Reliable Candle Data免费股票 OHLCV API
可靠 K 线数据指南
Choose, validate, and integrate free historical candle data without overlooking intervals, adjustments, rate limits, or usage rights.
选择、校验并接入免费的历史 K 线数据，
同时看清周期、复权、调用限额与使用权限。
Free stock OHLCV API: quick summary免费股票 OHLCV API 核心摘要
Time-series candles containing a timestamp plus open, high, low, close, and volume values for a symbol and interval.
Usually a limited quota, delayed coverage, shorter history, or non-commercial terms—not unlimited market data.
Exchange coverage, intervals, historical depth, time zone, split and dividend adjustments, missing bars, and rate limits.
Prototypes, education, research notebooks, charting demos, and low-frequency strategies with explicit data validation.
针对股票代码与周期返回时间序列，每根 K 线包含时间戳、开盘、最高、最低、收盘和成交量。
通常意味着有限配额、延迟行情、较短历史或非商业条款，并不等于无限制市场数据。
交易所覆盖、周期、历史深度、时区、拆股与分红复权、缺失 K 线和调用限额。
适用于原型、教学、研究 Notebook、图表演示和低频策略，但必须建立数据校验。
What OHLCV data meansOHLCV 数据代表什么
Each candle aggregates trading activity over an interval. Open is the first eligible trade, high and low are the interval extremes, close is the final eligible trade, and volume is the traded quantity. Provider rules can differ, so identical symbols and intervals may still produce different bars.
每根 K 线聚合一个周期内的交易活动：开盘价是首笔有效成交，最高价和最低价是区间极值，收盘价是最后一笔有效成交，成交量则是交易数量。供应商规则可能不同，因此同一代码与周期也可能得到不同 K 线。
Confirm whether timestamps mark the candle open or close, which time zone applies, and whether sessions include pre-market or after-hours trades.
Adjusted history may rewrite past prices after splits or dividends. Never mix raw and adjusted bars in one backtest.
Volume can represent shares, contracts, or another venue-specific unit. Some feeds omit or estimate it.
Expect holidays and halts, but investigate unexplained gaps, duplicate timestamps, zero-volume bars, and impossible high-low ranges.
Confirm whether intervals are left- or right-labeled, whether the ending timestamp is inclusive, and how partial current bars are marked. Boundary differences can duplicate or drop trades.
Bars from one venue, a consolidated feed, and adjusted vendor aggregates need not match. Condition codes determine which trades can set open, high, low, or close.
确认时间戳代表 K 线开始还是结束、使用哪个时区，以及是否包含盘前盘后交易。
拆股或分红后，复权数据可能改写历史价格。回测中绝不能混用原始 K 线与复权 K 线。
成交量可能代表股数、合约数或交易场所特定单位，部分数据源也可能缺失或估算该字段。
节假日和停牌属于正常情况，但应排查无原因缺口、重复时间戳、零成交量和不可能的高低价范围。
确认周期采用左标签还是右标签、结束时间是否包含在内，以及当前未完成 K 线如何标记。边界定义不同会造成成交重复或遗漏。
单场所 K 线、合并行情和供应商调整后的聚合结果不一定相同。成交条件代码会决定哪些成交可用于开、高、低、收。
Compare free OHLCV API options如何比较免费 OHLCV API
| Layer层级 | Main job主要作用 | Best for适合场景 | Boundary边界 |
|---|---|---|---|
| End-of-day feed日线数据源 | Daily candles after the session closes.收盘后提供日 K 线。 | Research, screening, and long-horizon models.研究、筛选和长周期模型。 | Not suitable for intraday decisions.不适合日内决策。 |
| Intraday REST API日内 REST API | Minute or hourly bars requested on demand.按需请求分钟或小时 K 线。 | Charts, alerts, prototypes, and backfills.图表、提醒、原型和历史补录。 | Free quotas may be easy to exhaust.免费配额可能很快耗尽。 |
| Bulk CSV download批量 CSV 下载 | Large historical extracts in files.以文件形式提供大批量历史数据。 | Notebooks, archives, and reproducible research.Notebook、归档和可复现研究。 | Updates may be delayed or manual.更新可能延迟或需要手动执行。 |
| Streaming feed流式数据源 | Live trades or aggregates over a persistent connection.通过长连接推送实时成交或聚合数据。 | Live dashboards and event-driven systems.实时看板和事件驱动系统。 | Real-time exchange rights are rarely fully free.实时交易所授权很少完全免费。 |
Request explicit non-overlapping windows, then verify the first and last timestamp of every page. Cursor and inclusive-date semantics often create duplicate boundary bars.
Aggregate a sample of smaller bars into hourly or daily candles and compare OHLCV. Differences reveal session boundaries, excluded trades, rounding, or missing input bars.
A provider may emit an empty interval with carried-forward prices, omit it entirely, or return nulls. Choose one internal policy and never interpret synthetic bars as trades.
Late trades and corrections can revise bars after the interval closes. Re-fetch a bounded overlap and version material changes rather than assuming old candles are immutable.
使用明确且不重叠的时间窗口，并核对每一页首尾时间戳。游标规则和包含结束日期的语义，常会在分页边界生成重复 K 线。
抽取较小周期 K 线，重新聚合为小时线或日线后比较 OHLCV。差异通常能暴露交易时段边界、被排除的成交、舍入或输入缺口。
供应商可能生成价格沿用的空周期、完全省略该周期，或返回空值。内部必须统一规则，也不能把合成 K 线误解为真实成交。
迟到成交和更正可能在周期结束后改写 K 线。应重新拉取有限重叠区间，并记录重要变化，而不是假设旧 K 线永远不变。
Use QVeris to find OHLCV capabilities用 QVeris 查找 OHLCV 能力
There is no single verified QVeris result dedicated to every stock OHLCV interval and market. Use the QVeris documentation to understand the capability layer and the Playground to inspect candidates before validating candle semantics with the provider.
目前没有一个经过核实的 QVeris 结果，可以覆盖所有股票市场和 OHLCV 周期。先通过 QVeris 文档了解能力调用方式，再到 Playground 检查候选项，最后向供应商核实 K 线语义。
- Search by capability instead of hardcoding a provider before requirements are clear.
- Inspect parameters and response schemas before wiring data into a chart or strategy.
- Keep provider attribution and request context attached to downstream results.
- 在需求明确前按能力搜索，而不是先绑定某一家供应商。
- 接入图表或策略前，先检查参数与响应字段。
- 让供应商署名与请求上下文始终跟随下游结果。
FAQ常见问题
Several providers offer free tiers, but they usually limit requests, history, exchanges, intervals, or commercial rights. Treat “free” as a plan constraint, not a data-quality guarantee.
Yes for learning and prototypes if you check survivorship bias, delisted symbols, corporate actions, missing bars, time zones, and whether the history is point-in-time correct.
They may use different venues, eligible-trade rules, interval boundaries, sessions, corrections, or adjustment methods. Compare metadata before choosing a winner.
Only with an explicit provisional flag. Replace them after the interval closes and retain event or retrieval timestamps so downstream code knows which version it used.
一些供应商提供免费套餐，但通常限制调用量、历史、交易所、周期或商业使用权。“免费”是套餐约束，不是数据质量保证。
可用于学习和原型，但应检查生存者偏差、退市股票、公司行动、缺失 K 线、时区和历史数据是否满足时点正确性。
它们可能采用不同场所、有效成交规则、周期边界、交易时段、更正或复权方法。判断对错前应先比较元数据口径。
可以，但必须明确标记为临时值，并在周期结束后替换；同时保留事件或采集时间，让下游知道使用的是哪个版本。
References and next steps参考资料与下一步
Alpha Vantage API documentation
Alpaca market data documentation
Twelve Data API documentation
QVeris documentation
QVeris Playground
Alpha Vantage API 文档
Alpaca 市场数据文档
Twelve Data API 文档
QVeris 文档
QVeris Playground