Roundglass Sustain emails

roundglasssustain.com

Roundglass Sustain sends about 1 email a week through HubSpot, most often on Friday around 5 AM Eastern.

Early figures, based on 13 emails received from Mar 20 to Oct 9, 2026.

ESP: HubSpot
Emails a week: about 1
Busiest send time: Fridays at 5am ET
Last sent: 25 days ago · Oct 9
Tracked since: Mar 2026
Emails collected: 13
Website popularity: Top 1 million sites

Recent emails

Browse all 13 emails

Oct 9, 2026 1:32 AM
, a letter from our outreach and impact manager
Sep 25, 2026 7:13 AM
, a letter from our editor

Recent subject lines

All subject lines

Subject lines average 42 characters. Each one opens the email it came from.

Sent (Eastern)	Subject	Preview text
Oct 9, 2026 1:32 AM	, a letter from our outreach and impact manager	Rithika Fernandes tells you about our Nature Learning Guides
Sep 25, 2026 7:13 AM	, a letter from our editor	Musings from the mountains of Uttarakhand
Aug 7, 2026 5:40 AM	User, are termites pests or ecosystem engineers?	User, are termites pests or ecosystem engineers? 96 While a few termite species are pests…
Jul 24, 2026 5:41 AM	User, does size matter in the animal kingdom?	User, does size matter in the animal kingdom? 96 These land-based giants shape India’s…
Jul 10, 2026 5:41 AM	User, discover a little-known sanctuary in Kerala	User, discover a little-known sanctuary in Kerala 96 Shendurney Wildlife Sanctuary lies in…
Jun 26, 2026 5:44 AM	User, meet India’s fastest land animals	User, meet India’s fastest land animals 96 They are masters of the chase and escape…
Jun 12, 2026 5:43 AM	User, turtles find a safe home in Alappuzha	User, turtles find a safe home in Alappuzha 96 Local communities join hands to protect…
May 29, 2026 5:45 AM	User, Kerala’s largest lake is in crisis	User, Kerala’s largest lake is in crisis 96 Vembanad lake's future hangs in the balance as…

All subject lines

When Roundglass Sustain sends

77% of its emails arrive in the 5 AM hour. Fridays are the busiest day.

Emails by weekday and hour, US Eastern
	12a	1a	2a	3a	4a	5a	6a	7a	8a	9a	10a	11a	12p	1p	2p	3p	4p	5p	6p	7p	8p	9p	10p	11p
Mon	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Tue	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Wed	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Thu	0	0	0	0	0	0	0	0	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Fri	0	1	0	0	0	10	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sat	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sun	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

Emails by hour and weekday, US Eastern
	Mon	Tue	Wed	Thu	Fri	Sat	Sun
12a	0	0	0	0	0	0	0
1a	0	0	0	0	1	0	0
2a	0	0	0	0	0	0	0
3a	0	0	0	0	0	0	0
4a	0	0	0	0	0	0	0
5a	0	0	0	0	10	0	0
6a	0	0	0	0	0	0	0
7a	0	0	0	0	1	0	0
8a	0	0	0	0	0	0	0
9a	0	0	0	1	0	0	0
10a	0	0	0	0	0	0	0
11a	0	0	0	0	0	0	0
12p	0	0	0	0	0	0	0
1p	0	0	0	0	0	0	0
2p	0	0	0	0	0	0	0
3p	0	0	0	0	0	0	0
4p	0	0	0	0	0	0	0
5p	0	0	0	0	0	0	0
6p	0	0	0	0	0	0	0
7p	0	0	0	0	0	0	0
8p	0	0	0	0	0	0	0
9p	0	0	0	0	0	0	0
10p	0	0	0	0	0	0	0
11p	0	0	0	0	0	0	0

FewerMore(busiest cell: 10 emails)

Based on 13 emails received from Mar 20 to Oct 9, 2026. Times in US Eastern. How we collect · When all brands send

How often Roundglass Sustain sends

Complete months have run between 1 and 3 emails.

March 2026: 1 email
April 2026: 2 emails
May 2026: 3 emails
June 2026: 2 emails
July 2026: 2 emails
August 2026: 1 email
September 2026: 1 email
October 2026: 1 email
November 2026: 0 emails

Based on 13 emails received from Mar 20 to Oct 9, 2026. Times in US Eastern. How we collect

Busiest month: May 2026, 3
Quietest month: Oct 2026, 1
Busiest day: Friday, 12
Quietest day: Monday, 0

About Roundglass Sustain

ESP: HubSpot
Website popularity (CrUX): Top 1 million sites
Tracked since: Mar 2026
Emails collected: 13
Emails a week: about 1
Last sent: Oct 9, 2026
Sends from: sustain@roundglass.com
Subject length: 42 characters avg

Counts include automated emails such as a welcome series. Website popularity is the bracket the brand's site falls in by visits, from Google's public Chrome UX Report (CrUX).

Similar sending frequency

Brand	ESP	Emails a week	Busiest day	Last sent
Careington Special Offerscareington.com	HubSpot	about 1	Wednesday	Oct 27, 2026	HubSpot · about 1 a week · busiest Wednesday · last sent Oct 27, 2026
Court Square Groupcourtsquaregroup.com	HubSpot	about 1	Wednesday	Oct 13, 2026	HubSpot · about 1 a week · busiest Wednesday · last sent Oct 13, 2026
Culture Groupculturegroup.asia	HubSpot	about 1	Thursday	Oct 29, 2026	HubSpot · about 1 a week · busiest Thursday · last sent Oct 29, 2026

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Every brand on HubSpot

Report an errorLast updated Nov 3, 2026

Roundglass Sustain emails

Recent emails

, a letter from our outreach and impact manager

, a letter from our editor

Recent subject lines

Archive

September 2026 1 email

When Roundglass Sustain sends

How often Roundglass Sustain sends

About Roundglass Sustain

Similar sending frequency

More brands on HubSpot

Get the Black Friday insights

	12a	1a	2a	3a	4a	5a	6a	7a	8a	9a	10a	11a	12p	1p	2p	3p	4p	5p	6p	7p	8p	9p	10p	11p
Mon	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Tue	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Wed	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Thu	0	0	0	0	0	0	0	0	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Fri	0	1	0	0	0	10	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sat	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sun	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

	Mon	Tue	Wed	Thu	Fri	Sat	Sun
12a	0	0	0	0	0	0	0
1a	0	0	0	0	1	0	0
2a	0	0	0	0	0	0	0
3a	0	0	0	0	0	0	0
4a	0	0	0	0	0	0	0
5a	0	0	0	0	10	0	0
6a	0	0	0	0	0	0	0
7a	0	0	0	0	1	0	0
8a	0	0	0	0	0	0	0
9a	0	0	0	1	0	0	0
10a	0	0	0	0	0	0	0
11a	0	0	0	0	0	0	0
12p	0	0	0	0	0	0	0
1p	0	0	0	0	0	0	0
2p	0	0	0	0	0	0	0
3p	0	0	0	0	0	0	0
4p	0	0	0	0	0	0	0
5p	0	0	0	0	0	0	0
6p	0	0	0	0	0	0	0
7p	0	0	0	0	0	0	0
8p	0	0	0	0	0	0	0
9p	0	0	0	0	0	0	0
10p	0	0	0	0	0	0	0
11p	0	0	0	0	0	0	0

	12a	1a	2a	3a	4a	5a	6a	7a	8a	9a	10a	11a	12p	1p	2p	3p	4p	5p	6p	7p	8p	9p	10p	11p
Mon	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Tue	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Wed	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Thu	0	0	0	0	0	0	0	0	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Fri	0	1	0	0	0	10	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sat	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sun	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

	Mon	Tue	Wed	Thu	Fri	Sat	Sun
12a	0	0	0	0	0	0	0
1a	0	0	0	0	1	0	0
2a	0	0	0	0	0	0	0
3a	0	0	0	0	0	0	0
4a	0	0	0	0	0	0	0
5a	0	0	0	0	10	0	0
6a	0	0	0	0	0	0	0
7a	0	0	0	0	1	0	0
8a	0	0	0	0	0	0	0
9a	0	0	0	1	0	0	0
10a	0	0	0	0	0	0	0
11a	0	0	0	0	0	0	0
12p	0	0	0	0	0	0	0
1p	0	0	0	0	0	0	0
2p	0	0	0	0	0	0	0
3p	0	0	0	0	0	0	0
4p	0	0	0	0	0	0	0
5p	0	0	0	0	0	0	0
6p	0	0	0	0	0	0	0
7p	0	0	0	0	0	0	0
8p	0	0	0	0	0	0	0
9p	0	0	0	0	0	0	0
10p	0	0	0	0	0	0	0
11p	0	0	0	0	0	0	0

	12a	1a	2a	3a	4a	5a	6a	7a	8a	9a	10a	11a	12p	1p	2p	3p	4p	5p	6p	7p	8p	9p	10p	11p
Mon	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Tue	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Wed	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Thu	0	0	0	0	0	0	0	0	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Fri	0	1	0	0	0	10	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sat	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sun	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

	Mon	Tue	Wed	Thu	Fri	Sat	Sun
12a	0	0	0	0	0	0	0
1a	0	0	0	0	1	0	0
2a	0	0	0	0	0	0	0
3a	0	0	0	0	0	0	0
4a	0	0	0	0	0	0	0
5a	0	0	0	0	10	0	0
6a	0	0	0	0	0	0	0
7a	0	0	0	0	1	0	0
8a	0	0	0	0	0	0	0
9a	0	0	0	1	0	0	0
10a	0	0	0	0	0	0	0
11a	0	0	0	0	0	0	0
12p	0	0	0	0	0	0	0
1p	0	0	0	0	0	0	0
2p	0	0	0	0	0	0	0
3p	0	0	0	0	0	0	0
4p	0	0	0	0	0	0	0
5p	0	0	0	0	0	0	0
6p	0	0	0	0	0	0	0
7p	0	0	0	0	0	0	0
8p	0	0	0	0	0	0	0
9p	0	0	0	0	0	0	0
10p	0	0	0	0	0	0	0
11p	0	0	0	0	0	0	0