<div dir="ltr">Hi there,<div>I would like to ask for your opinion and help with 2 questions.</div><div>1) is CRS 4326 suitable to make precise area calculations of agriculture field boundaries that vary from 2 to 100ha for the 2nd decimal of a hectare<span style="background-color:rgb(248,248,248);color:rgb(29,28,29);font-family:Slack-Lato,Slack-Fractions,appleLogo,sans-serif;font-size:15px;font-variant-ligatures:common-ligatures">?</span>. I am aware that CRS 4326 is supposed to have relatively precise area calculation at the equator and the higher the latitude, the less precise the area calculation is. But we ran a test in QGIS and outside QGIS with Python code and benchmarked around 30K fields from North America, South America and Europe with relatively high latitudes (Canada and Finland). The avg area difference of the sum of all fields was in the 9th decimal of a hectare between area calculation with CRS 4326 and area calculation with regional equal area CRS for each region. Even Canada and Finland had that area difference of a  9th decimal. Therefore we concluded that CRS 4326 is suitable for precise area calculation for 2 decimals of a hectare for agriculture fields, independently of the latitude. Are we on the right track? It seems that QGIS and Python use formulas that correctly convert degrees into metric area calculation and minimize the effect of different latitudes. Any kind of insights would be greatly appreciated.</div><div>2) We would like to know which formula is being used in QGIS to do the area calculation... Does someone know and could share the formula with us

<span style="color:rgb(29,28,29);font-family:Slack-Lato,Slack-Fractions,appleLogo,sans-serif;font-size:15px;font-variant-ligatures:common-ligatures;background-color:rgb(248,248,248)">?</span></div><div><font color="#1d1c1d" face="Slack-Lato, Slack-Fractions, appleLogo, sans-serif"><span style="font-size:15px;font-variant-ligatures:common-ligatures"><br></span></font></div><div><font color="#1d1c1d" face="Slack-Lato, Slack-Fractions, appleLogo, sans-serif"><span style="font-size:15px;font-variant-ligatures:common-ligatures">Thank you for your attention.</span></font></div><div><font color="#1d1c1d" face="Slack-Lato, Slack-Fractions, appleLogo, sans-serif"><span style="font-size:15px;font-variant-ligatures:common-ligatures">Best,</span></font></div><div><font color="#1d1c1d" face="Slack-Lato, Slack-Fractions, appleLogo, sans-serif"><span style="font-size:15px;font-variant-ligatures:common-ligatures">Gabor<br clear="all"></span></font><div><br></div><span class="gmail_signature_prefix">-- </span><br><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><span></span><span></span><table cellpadding="0" cellspacing="0" border="0" style="color:rgb(0,0,0);font-family:"Google Sans",Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:medium;background:none;border:0px;margin:0px;padding:0px"><tbody><tr><td style="font-family:Helvetica,Arial,sans-serif;color:rgb(61,67,68);font-size:12px"><b><br><br></b></td></tr></tbody></table><span><p dir="ltr" style="line-height:1.56;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(34,34,34);background-color:transparent;font-weight:700;vertical-align:baseline">Dr. Gabor Szakacs</span><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(34,34,34);background-color:transparent;font-weight:700;vertical-align:baseline"><br></span><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(19,79,92);background-color:transparent;vertical-align:baseline">Geospatial Analyst in Regenerative Agriculture</span></p><p dir="ltr" style="line-height:1.56;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(34,34,34);background-color:transparent;vertical-align:baseline">+55 11 989319305</span></p><p dir="ltr" style="line-height:1.56;margin-top:0pt;margin-bottom:0pt"><span style="font-size:8pt;font-family:Arial,sans-serif;color:rgb(19,79,92);background-color:transparent;vertical-align:baseline"><a href="mailto:gabor.szakacs@agreena.com" target="_blank">gabor.szakacs@agreena.com</a></span></p><br><p dir="ltr" style="line-height:1.56;margin-top:0pt;margin-bottom:0pt"><a href="https://agreena.com/" target="_blank"><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(17,85,204);background-color:transparent;vertical-align:baseline"><span style="border:none;display:inline-block;overflow:hidden;width:131px;height:35px"><img src="https://lh3.googleusercontent.com/HAYhoxGSnZE-f86DrpwIRP9ZpFrgoV7bKPgx-VPQK6bhSmFn-Y4qBFbIlawLDySqrV6naScXxfq83VxZzOcNjqHfxvc3mU6_-aN6LF-5obWS7P7zWBSaCHZZnhXeq8f4MP6DDHvlItY-c0HZo45EBEk" width="131" height="35" style="margin-left:0px;margin-top:0px"></span></span></a></p><p dir="ltr" style="line-height:1.56;margin-top:0pt;margin-bottom:0pt"><a href="https://agreena.com/" target="_blank"><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(17,85,204);background-color:transparent;vertical-align:baseline"><span style="border:none;display:inline-block;overflow:hidden;width:31px;height:31px"><img src="https://lh6.googleusercontent.com/y3oY91zBUXpuadUzy_oJT9pgPRU-dS6mFo9dL7kx55esAHz6KYBBRCT8d63snGVsogW9_yvcGj1sYs4bFpQnqKnZzGjtEaZCUgddsE_qfxIoLcRWLZeWBG8aukK3_k8QmTffy1QkXtmfCTnE4Ucqf4c" width="31" height="31" style="margin-left:0px;margin-top:0px"></span></span></a><a href="https://www.linkedin.com/company/agreena" target="_blank"><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(17,85,204);background-color:transparent;vertical-align:baseline"><span style="border:none;display:inline-block;overflow:hidden;width:31px;height:31px"><img src="https://lh5.googleusercontent.com/2yrRFXGNRb-iKeFOBfz-LyhTM_ZmaoFAQQ6hyJtsiAXFDpYMP0P1UIPNpQCkb68pHmEIirlVZo1XQ76RIeHQZtxCw1FxtIgeLEkDtr9BRa3KyPBQ0jq99cI1o7CtmrUB7F3P9lKZauElbnsBP5wGOhY" width="31" height="31" style="margin-left:0px;margin-top:0px"></span></span></a><a href="https://twitter.com/AgreenaApp" target="_blank"><span style="font-size:11pt;font-family:Arial,sans-serif;color:rgb(17,85,204);background-color:transparent;vertical-align:baseline"><span style="border:none;display:inline-block;overflow:hidden;width:31px;height:31px"><img src="https://lh5.googleusercontent.com/EobDIZhX8ILtElOTXzzOV1TFYdEocybzLwSwcani9kH-xn4P4Bpy4hOG9b2tfd9nToB3rC9ypX7YLf_sB-CMaGIEESjZYyJcWFXHUuGtGbUxqWuEtWM9f2T9E4xMBRi3rtlfOGDHAD_IIbwYk9GUNlI" width="31" height="31" style="margin-left:0px;margin-top:0px"></span></span></a><a href="https://www.instagram.com/agreenaapp/" ta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