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Print · October 2026 Edition

Sendoso vs Thanks.io

Three of fourteen models named Sendoso first on the direct prompt; zero named Thanks.io. Sendoso was named by thirteen of the fourteen models and Thanks.io by ten and Sendoso carries 36 labels and Thanks.io 11, so the shares are not directly comparable.

Sendoso

criticized challenger

Named in two categories this edition.

Thanks.io

accepted challenger

founded 2017. Named in two categories this edition.

First-choice share6%4%Of first choices across the direct, paraphrase, budget and scale prompts, 0 to 100.

Negative rate28%0%Negative labels as a share of the product's labels, 0 to 100.

Rank in category#3#6A position in a field of 10; printed, not drawn.

Labels3611A count; the two differ.

The two percentage rows are drawn on one 0 to 100 track, Sendoso reading right to left. Rank and label count are printed, not drawn.Postalytics was named alongside these two in nine of the fourteen direct answers. Postalytics vs Sendoso · Postalytics vs Thanks.io · Lob vs Sendoso

Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all fourteen models, for a mid-market B2B company; rank is within the category; every quote names the model and the prompt it came from. Both figures come from the print page.

By framing

How many of the fourteen models made each the first choice, per way of asking, and how many argued against it.

SendosoFirst choices, of fourteen modelsThanks.io

Direct301 against Sendoso

Paraphrase001 against Sendoso

Comparative001 against Sendoso

Budget-constrained02

Scale-constrained00

Negative007 against Sendoso

Bars are first choices, 0 to 14 each sideModels that argued againstA model can name both, so the two sides of a row do not sum to fourteen.

Every model, every framing

The eighty-four answers behind the chart above, one cell each: where Sendoso and Thanks.io stood in it.

Model	Direct	Paraphrase	Comparative	Budget-constrained	Scale-constrained	Negative
Claude Haiku 4.5
GPT-5.4 mini
Gemini 3.5 Flash
Perplexity Sonar
Grok 4.1 Fast
Mistral Small
DeepSeek V4 Flash
Llama 4 Maverick
Qwen 3.7 Flash
Kimi K2
GLM 4.7 FlashX
MiniMax M2.5
GPT-6 Luna
Muse Glimmer 30B

Sendoso

Thanks.io

first choice

named as an alternative

argued againstblank: not namedEach cell is one answer, Sendoso on the left and Thanks.io on the right.

The direct prompt

The plain question, one answer per model, grouped by where Sendoso and Thanks.io stood in it.

Sendoso first, Thanks.io not the choice

3 of 14 modelsThanks.io was named in the answer but not as the choice, or not at all.

GPT-5.4 miniSendoso alternatives: PFL

Grok 4.1 FastSendoso alternatives: Lob, PostGrid Print & Mail

Qwen 3.7 FlashSendoso alternatives: CIENCE, Cobro, Lob, PebblePost

Neither was the first choice, one was named

5 of 14 modelsThe answer put something else first and named one of the two as an alternative.

Claude Haiku 4.5Postalytics alternatives: Lob, Sendoso

Gemini 3.5 FlashReachdesk alternatives: Alyce, Lob, PostGrid, Postal, Postalytics, Sendoso

DeepSeek V4 FlashPostalytics alternatives: Lob, PFL, Postal, Postie, Sendoso

GLM 4.7 FlashXPostalytics alternatives: Lob, PostGrid, Postal, Sendoso

Muse Glimmer 30BPFL - Printing For Less alternatives: Lob, Postal, Postalytics, Reachdesk, Sendoso

Neither was named

6 of 14 modelsThe answer made no first choice from these two in this category.

Perplexity SonarPostGrid alternatives: Reachdesk

Mistral SmallPostie alternatives: PFL, Postalytics

Llama 4 MaverickPostie alternatives: Postal

Kimi K2Lob, Postal alternatives: PFL, Postalytics

MiniMax M2.5Postalytics alternatives: PFL Direct Mail Platform

GPT-6 LunaPostalytics alternatives: Lob, Postal, Reachdesk

Bold names in an answer are the products the judge labeled a first choice; a model naming several gives each of them that label. The full answer text for every row is in the record.

By buyer segment

The same question asked on behalf of a different buyer. Each standing is computed within its segment and they are never added together. The figures above are the mid-market standing, which is the one the category orders by.

Small business

Sendoso leads by two points.

Sendoso#6 of 9

Thanks.io#7 of 9

The full small business standing →

Mid-marketThe figures above

Sendoso leads by two points.

Sendoso#3 of 10

Thanks.io#6 of 10

The full mid-market standing →

Enterprise

Sendoso leads by thirteen points.

Sendoso#2 of 8

Thanks.io#– of 8

The full enterprise standing →

What the models said about Sendoso

Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Two of two in this category shown.

“Several AI models recommend avoiding it for direct mail automation due to negative feedback and limitations in scalability and pricing transparency.” Mistral Small · negative prompt · hard negative

“Sendoso is the biggest platform to avoid unless you have a massive budget and can tolerate poor support.” Kimi K2 · negative prompt · hard negative

What the models said about Thanks.io

Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Two of two in this category shown.

“Click2Mail or thanks.io (pay-as-you-go plan) stand out as the best direct mail automation platforms” Grok 4.1 Fast · budget prompt · first choice

“Thanks.io is the gold standard for low-budget operations.” Gemini 3.5 Flash · budget prompt · first choice

Also compared

Postalytics vs Sendoso Postalytics vs Thanks.io Lob vs Sendoso Lob vs Thanks.io Sendoso vs Click2Mail Sendoso vs Postie Sendoso vs PostGrid Sendoso vs Reachdesk Click2Mail vs Thanks.io Postie vs Thanks.io Thanks.io vs PostGrid Thanks.io vs Reachdesk All twenty-eight head-to-head pages and the full direct mail standing

Comparisons are drawn for the top eight products in each category, each against each. The output is the models' output; nothing here is a recommendation by the index.