Thank-You Email
Work & EmailWriting
Name the person and exactly what they helped with, and get a sincere thank-you email that is not overdone.
Fill the blanks and it copies as you filled it
Write a thank-you email to someone who helped me. - Recipient & relationship: - What I'm thankful for: - Tone: - Output: body in paragraphs, not overly formal
0 of 4 blanks filled · anything left blank copies with its brackets
What this prompt does
Compared with asking the same thing without the length and format lines.estimate
Estimated output tokens
1,400
Asked loosely
1,400
This prompt
Energy (Wh)
1.215
Asked loosely
1.215
This prompt
Tokens estimated from characters; energy measured by Jegham et al. 2025.
A shorter answer, but the same energy band — the measurements are per band.
Reported backfire — Specifying output lengthSpecifying a length longer than needed backfires (a 34% increase in 11% of scenarios)
Where these figures come from
Published figures for the rule itself — not what this prompt saves.
Specifying output length
38.7%mean reduction · 95% CI 29.7–47.7%
Podder et al. 2026 BP#5 · 18 use cases / 57 prompts
by modelGPT-4o 35%Command R+ 49%Mistral-7B 32%
Reduced in every scenario. No backfire reported