A conversation coach that takes the temperature of your words
How warm were my words today?
For the moments when talking is hard, Malondo helps you find the one or two sentences to say to this person, right now. It reads the pitch, pace, pauses and loudness of your voice on your device and measures the temperature of your words.
Six tones sit on one line. Plain, at 36.5℃, is the origin, and while you speak the needle moves like this.
For moments like these
When you owe an apology and the first sentence won't come.
When you want to say no but worry about what it will cost.
When you mean to comfort someone and fear you'll scratch instead.
Those one or two sentences are what Malondo thinks through with you. It never sends anything for you. You choose, shape it in your own words, and send it yourself.
On screen
A place to measure, to say it, and to let it out
Swipe through. Thirteen scenes.
How warm were my words today?
Each day's temperature settles into the calendar
Who you spoke with, how often, and how warm
This month, this week and today on one card
Pick a target temperature and talk for 20 seconds
Your voice is heard only on your device
While you speak, the temperature moves live
You see at once whether you're cooler or hotter than the target
How close you came to the target, at a glance
Five axes, from steadiness to speech and pauses
Listen again and follow the flow of temperature
The recording is deleted the moment you leave
Days you need words, and days you need to unwind first
The Talk tab opens four ways
What you could say to this person, right now
Four sentences fitted to the situation and the temperature
Practise the suggestion out loud
Speaking practice at the target temperature
What you couldn't tell anyone — write it, and a letter comes back
Nothing you write here is kept
One thing that stayed too long — let it go, no reply needed
The text is never written to a file
Keep the sentences you like and bring them back
Filter by person, search the text, pin the ones you use most
Four languages, two units
The screen and the sentences it writes, in your language
To this person, in my own voice, what one or two sentences should I say?
An app built to answer just this one question
A favour, a refusal, an apology, comfort, a conflict. The words are already in you, but the first sentence won't come, and you sit with the window open for far too long. That is the moment this is for. The app never sends anything for you. You choose, shape it in your own words, copy it, and send it yourself.
What to sayPick who, what and in which tone, write a line or two about what happened, and four sentences arrive, each taking a different road. Every card says why it speaks this way, what to say when they answer, and what to watch out for. Something you already wrote can be reworked so the meaning stays and only the phrasing changes; a card you like can be reworked again — shorter, softer — and Practise lets you walk through what comes after.
Unwind firstOn days when you don't need words yet, write what happened and choose only what kind of answer you need. Just listen · Help me sort it out · Show me another angle · Tell me what to do · What's mine to carry. A letter comes back. Neither what you wrote nor the reply is kept.
Letting goWrite one thing that has stayed too long, in a hundred characters or fewer, and erase it by hand, with no reply. As you press and hold, the words blur, run like ink or slip away like sand. Nothing is generated, so not one character leaves the device or is ever written to a file. All that remains is a dot on the calendar. No daily limit, no ads.
Today's squareOn days when you don't choose any words, this is enough. Pick how you felt today and how warm you spoke, and it goes into the calendar. One square per day, so changing it later changes that one square and nothing else.
MeasureSpeak out loud for about twenty seconds, and the volume, pauses and pitch of your voice are read on your device to measure the temperature of your words. When you finish, a fingerprint stands up: your voice's texture laid over the target's on five axes. Instead of a score, it names one thing to try next.
Look back · Who you spoke withThe day after you say something, look back on how it went with one of three answers: It eased a little · About the same · It got harder. The Who-you-spoke-with card gathers this month, this week and today on one card — who, how many times, and how warm. Someone you haven't spoken to yet is marked 'None', not 0.
Four languages
The screen and the sentences it writes, in the same language
한국어 · English · 日本語 · Español. By default it follows your device, and you can change it in the drawer under Language and units.
Tap a phone and this page switches to that language too.
More than the screen changes
The four sentences, the letter, the daily reminder and the home widget all come in the language you chose. Register — formal and informal, です・ます — follows each language's own grammar. What you wrote yourself is never translated; it stays exactly as you typed it.
℃ or °F, your choice
Every value you measure or choose is always stored in Celsius; only what you see changes. So switching units leaves your history untouched. You can try it on this page too.
Word temperature
Not body heat — a temperature given to the texture of speech
Six tones, each given a temperature from cool to warm. Plain, at 36.5℃, is the origin. Move left and the words cool; move right and they warm. The temperature you pick when choosing a sentence and the one measured from your voice share the same six stops and the same scale, so you can compare them directly.
35.0℃FirmSteady, clear, unwavering
35.7℃CalmLow and evenly settled
36.5℃PlainoriginSimple, with nothing extra
37.1℃LightA light, quick rhythm
37.7℃CaringReading the other person first
38.2℃WarmWarmth you can hear
Inside the app, temperature is never carried by colour alone. Colour, number, name and the shape of the line all speak together.
How it measures
From sound to temperature, in six steps
While you record, the needle looks at the last 4.5 seconds and moves on any sound that rises above the room's noise floor. When you stop, the whole take is measured once more and that value is kept. All that remains per take is one temperature and a timestamp.
① Every 70 ms, it reads loudness and pitch.The three voices are synthesized; the numbers are what the app's own analysis code measured from them.
It listens
It reads one frame every 70 ms. Each frame carries the loudness (dBFS), the pitch found by autocorrelation (Hz), the share of the voice band (300–3400 Hz), and seven 10 ms loudness values inside the frame.
every 70 ms · loudness dBFS · pitch Hz · 10 ms loudness × 7
It removes the room and finds speech
It tracks the room's noise floor throughout the recording and measures whatever rises above it. Where the voice band and the 3-to-5-per-second rhythm of syllables appear together, it marks speech and reads pitch only there. From the frames that remain, the room's share is subtracted.
x′ = 10·log10( 10x/10 − 10floor/10 ) — never trimming more than 12 dB
It measures five things in human units
Before any scoring, it measures in the units people use. Pitch range is the spread in semitones around your own middle pitch, so high and low voices share one scale. Pace is the number of peaks separated by dips in the 10 ms loudness (the vowels of syllables) divided by the time sound was heard; pauses are the silent share from the first word to the last; loudness is the room-subtracted average, and even volume is its spread.
pitch range = σ( 12·log2( f / f̃ ) ) — semitones, f̃ is your middlepace = peaks ÷ time with sound — syllables/spauses = silent frames ÷ first word to lastloudness = μ(dBFS) · spread = σ(dB) — room subtracted
It places them on everyday reading
All five values go onto 0–100 by one rule. 50 is the median of 226 Korean readings (FLEURS) and one interquartile range is 25 points. So the middle half of ordinary reading falls between 37.5 and 62.5, and the references of the six tones stand inside the range people actually produce. Only the “usual” pitch follows the voice reference in the Tone tab (Default · Male · Female).
score = 50 + 25 × ( value − median ) ÷ IQR
It sums them into a temperature
Word temperature is the weighted sum of the five scores. Pitch decides most of it; loudness cools it a little (the louder and crisper, the closer to Firm); pauses warm it a little. Pace and even volume don't move the temperature — they only tell which of the six tones you are closest to, the shape of your texture. Because it is a sum, each measure pushes one way only, and the result always stays within 34.7℃–38.5℃.
temperature (℃) = 36.5 + 1.0·(pitch − 50)/25 − 0.25·(strength − 50)/25 + 0.1·(pauses − 50)/25pace × 0 · even volume × 0 — used only for the shape (match score)
It compares with your target and suggests one thing
Within 0.45℃ of the target counts as on target. Even the same person reading the same way varies from sentence to sentence, and a 15-second take wobbles by about 0.44℃ (one standard deviation) — so one reading is not used to separate neighbouring tones. Off target, it suggests the one measure with the largest weight × points left to the target. Each weight points one way only, so following the suggestion always moves the temperature toward the target.
on target = | temperature − target | ≤ 0.45℃ · suggestion = largest ( weight × points left )
36.5℃closest to Plain
Axis
Plain
Ordinary voice
Calm pace
50
45
Even volume
50
67
Speech and pauses
50
53
Vocal strength
50
50
Pitch
50
49
The fingerprint. The dashed line is Plain (all five at 50 — ordinary reading); the filled shape is the ordinary voice from the video. Pitch at 49 sets the temperature near 36.5℃, and how the five spread apart is the shape of the texture. The result screen uses the same drawing to lay your texture over the target's.
See the six reference textures
Tone
℃
Calm pace
Even volume
Speech and pauses
Vocal strength
Pitch
Firm
35.0
50
75
38
75
20
Calm
35.7
75
75
62
25
23
Plain
36.5
50
50
50
50
50
Light
37.1
25
25
31
69
72
Caring
37.7
69
62
69
38
75
Warm
38.2
62
50
56
38
89
Exactly the constants the app carries. Plain is ordinary reading (all five at 50); the other five were moved ½–1½ interquartile ranges in the direction their names describe, then their pitch value was solved from the temperature formula. How far they were moved is still a judgement, not a measurement.
See the values behind the scale
Measure
What is measured
50 points (median)
25 points (IQR)
Calm pace
Pace — counted syllables/s, slower is higher
5.24
0.56
Even volume
Loudness spread — smaller is higher
7.46 dB
2.19 dB
Speech and pauses
Pause share — more is higher
0.099
0.107
Vocal strength
Room-subtracted average loudness
−42 dBFS
6 dB
Pitch
Pitch range (semitones)
Male 2.56 Default 2.84 Female 3.12
Male 0.63 Default 0.69 Female 0.56
Measured with the app's own code on 226 Korean readings from FLEURS (CC-BY-4.0), each first set to an average of −42 dBFS. The corpus can't say what 50 points of loudness is, so −42 dBFS — the middle of what a phone held in the hand records in a quiet room — was set, with 25 points = 6 dB, the drop when the phone moves twice as far away. Pace counts about 0.8 of the real syllables, because syllables without a final consonant that run together merge into one; the scale was measured the same way, so that share cancels out.
Why temperature
Why does a voice yield a temperature?
It is not body temperature
Word temperature is a metaphor attached to the texture of speech. What is physically measured is five things — pitch range, pace, the share of pauses, loudness and its spread — all quantities a microphone can measure reliably, on the device.
Where it becomes a temperature is a declaration
Six tones are each given a temperature, and your voice goes through the same formula onto a number on one line. The references of the six tones were placed so that the formula returns their own temperatures, which is why the temperature you pick for a sentence and the one measured from your voice can be compared on the same scale.
It doesn't depend on the room or the pitch of your voice
Subtracting the noise floor puts a café and a bedroom on the same scale. Pitch is measured not as absolute frequency but as semitones from your own middle. Even so, in the same readings women used a wider pitch range (medians 2.56 vs 3.12 semitones), so choosing a voice reference in the Tone tab sets the “usual” pitch to that side. The default is halfway between. Holding the phone twice as close moves the temperature by only about 0.25℃.
The scale was tuned on human voices
The 50 of every measure is the median of 226 Korean readings, and Plain sits exactly there. The way pace is counted was also chosen against the real syllable counts of the scripts. How far to move the other five tones is still a judgement, and it will be corrected as recordings read in each tone come in.
What it won't do
This app is defined by what it chose not to do
It does not diagnose. Values read from loudness are never used to judge emotion, personality, mental health or the quality of a relationship. It is not a substitute for medical care or counselling.
It does not hand out report cards. The baseline on the chart is your own average, not 36.5℃. The only comparison is with yourself, so no grades appear. No scores, no streaks. Someone you haven't spoken to yet is marked 'None', not 0 — because 0℃ would mean you spoke very coldly.
It does not write sentences that manipulate. Not sentences to win or to persuade, but sentences that carry both your feelings and your boundaries.
It steps back in the face of danger. When signs of self-harm, violence or threats are read, guidance and helpline numbers come before any suggestion, and ads are closed on that screen.
It does not hoard your writing. There is no account, and what you write and what you receive are not kept on a server. Text in Letting go has no draft either — it is never written to a file on the device, and only the date and count remain. One tap on Delete everything removes the records on the device and the anonymous ID together.
Data
What leaves your device
Your voice never leaves the device. Loudness and frequency analysis happen entirely on it, and all that remains per take is one temperature and a timestamp. There are four ways anything leaves, and the app's data sheet shows the same list.
When sentences or a letter are writtenRelationship · goal · temperature · the situation or draft you wrote · your tone settings (sentence length · politeness · words to avoid) · the language you chose go to Google Gemini. One anonymous ID for this installation goes along to count the daily limit. Letting go and Today's square generate nothing, so nothing leaves.
When an ad is shownAdvertising identifier · device information · approximate location go to Google AdMob. Your situation and relationships are not sent.
When the app crashesOnly if you turned it on: where it crashed · device model · OS and app version go to Firebase. Nothing you wrote or received is included.
When it checks for a new versionIt only fetches one version table from this website. It sends nothing, not even the app version.
What never leavesRecordings and loudness · kept sentences · usage history · look-backs · per-person records · anything written in Letting go · the voice reference in the Tone tab.
Not storing and not sending are different promises, so the complete list of what leaves is in the privacy policy.
Questions
From apology texts to your tone of voice
What is Malondo?
An AI conversation coach for the moments when talking is hard. When the first sentence of an apology, a refusal, a request or a word of comfort won't come, it suggests four ways to say it to this person, right now. Speak out loud for about twenty seconds and it also measures the temperature of your tone of voice. It's free and needs no account.
What does 'the temperature of your words' mean?
The same words can land cold or warm depending on how you say them. Malondo gives that texture a temperature: Firm 35.0℃ · Calm 35.7℃ · Plain 36.5℃ · Light 37.1℃ · Caring 37.7℃ · Warm 38.2℃. The six tones sit on one line, so the temperature you pick for a sentence and the one measured from your voice share the same scale. It's a metaphor for how your words come across, not your body temperature.
I don't know how to write an apology text or say no.
In 'I want to find what to say', choose who (Spouse · Partner · Family · Friend · Coworker · Boss), what (Apologise · Say no · Ask a favour · Comfort · Ease a conflict · Say how I feel · Give my view) and in which tone, then write a line or two about what happened. Four sentences arrive, each taking a different road, and every card says why it speaks this way, what to say when they answer, and what to watch out for. Something you already wrote can go through 'Rework my sentence': the meaning stays and only the phrasing changes.
Can it help me reach out first after a fight, or find words of comfort?
Yes. That's what Ease a conflict, Comfort and Say how I feel are for. It doesn't write sentences to win or to persuade, but sentences that carry your feelings and your boundaries together, and Practise lets you walk through what may come next. The app never sends anything for you. You choose, shape it in your own words, copy it and send it yourself.
Can I tell whether my tone of voice sounds cold?
In Measure, speak out loud for about twenty seconds. Malondo reads the pitch, pace, pauses and loudness of your voice on your device and measures the temperature of your words. While you talk you see how close you are to the target temperature you picked, and at the end a fingerprint lays your voice over the target on five axes to show where they part. Instead of a score it names one thing to try next, so it also works as speaking practice: read a suggested sentence aloud and soften your tone.
I need somewhere to get something off my chest.
In 'Unwind first', write what happened and choose only what kind of answer you need (Just listen · Help me sort it out · Show me another angle · Tell me what to do · What's mine to carry), and a letter comes back. Neither what you wrote nor the reply is kept. On days you don't need a reply, Letting go lets you write one thing that has stayed too long, in a hundred characters or fewer, and erase it by hand, and Today's square keeps how you felt on the calendar.
Where do my recordings and my writing go?
Your voice never leaves the device. All analysis happens on it, and the recording is deleted as soon as you leave the result screen. There's no sign-up, and the situations you write and the sentences you receive are not kept on a server. Only while sentences or a letter are being made do the situation you wrote and the relationship, goal and temperature you picked go to Google Gemini. The full list of what leaves is in the privacy policy.
Is it free? Are there ads?
It's free, with no in-app purchases. You get three rounds of suggested sentences and two letters a day, and on days you use them up you can choose to watch one rewarded ad to refill. Letting go and Today's square have no limits and no ads.
Can it replace therapy or counselling?
No. Malondo is not a medical or counselling service, and it does not diagnose emotions, personality or relationships. When signs of self-harm or violence are read, guidance and helpline numbers come before any suggestion.
Is it on Android? Which languages does it speak?
Right now you can get it on iPhone (App Store); Android (Google Play) is on the way. Screens and suggested sentences come in 한국어 · English · 日本語 · Español, and temperatures can be shown in ℃ or °F.
Get it
On iPhone and Android, free
No in-app purchases. The only ad is one rewarded ad you open yourself, on days you've used up the daily allowance. Available in 한국어 · English · 日本語 · Español.
Malondo
